Minecraft crashing

Hi, i have spent alot of time to find staff that don't care or don't don't how to go to my empire and clear my inventory. So can u please clear my inventory on my empire because i have used a command that gave me my head and it's a part of 1.8 and then my minecraft crashes.(I think)

here is my minecraft crash log:

---- Minecraft Crash Report ----
// This doesn't make any sense!

Time: 30-04-15 16:13
Description: Rendering item

com.google.common.util.concurrent.UncheckedExecutionException: java.lang.NullPointerException
at com.google.common.cache.LocalCache$Segment.get(LocalCache.java:2201)
at com.google.common.cache.LocalCache.get(LocalCache.java:3934)
at com.google.common.cache.LocalCache.getOrLoad(LocalCache.java:3938)
at com.google.common.cache.LocalCache$LocalLoadingCache.get(LocalCache.java:4821)
at com.google.common.cache.LocalCache$LocalLoadingCache.getUnchecked(LocalCache.java:4827)
at bnq.a(SourceFile:126)
at bhl.a(SourceFile:76)
at bfj.a(SourceFile:52)
at bji.a(SourceFile:122)
at bji.a(SourceFile:312)
at bji.b(SourceFile:348)
at avp.a(GuiIngame.java:1059)
at avp.a(GuiIngame.java:378)
at avp.a(GuiIngame.java:154)
at bfl.a(EntityRenderer.java:1288)
at avf.av(SourceFile:914)
at avf.a(SourceFile:325)
at net.minecraft.client.main.Main.main(SourceFile:124)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:483)
at net.minecraft.launchwrapper.Launch.launch(Launch.java:131)
at net.minecraft.launchwrapper.Launch.main(Launch.java:27)
Caused by: java.lang.NullPointerException
at com.mojang.authlib.yggdrasil.YggdrasilMinecraftSessionService.isWhitelistedDomain(YggdrasilMinecraftSessionService.java:210)
at com.mojang.authlib.yggdrasil.YggdrasilMinecraftSessionService.getTextures(YggdrasilMinecraftSessionService.java:149)
at bnq$1.a(SourceFile:47)
at bnq$1.load(SourceFile:44)
at com.google.common.cache.LocalCache$LoadingValueReference.loadFuture(LocalCache.java:3524)
at com.google.common.cache.LocalCache$Segment.loadSync(LocalCache.java:2317)
at com.google.common.cache.LocalCache$Segment.lockedGetOrLoad(LocalCache.java:2280)
at com.google.common.cache.LocalCache$Segment.get(LocalCache.java:2195)
... 23 more


A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------

-- Head --
Stacktrace:
at com.google.common.cache.LocalCache$Segment.get(LocalCache.java:2201)
at com.google.common.cache.LocalCache.get(LocalCache.java:3934)
at com.google.common.cache.LocalCache.getOrLoad(LocalCache.java:3938)
at com.google.common.cache.LocalCache$LocalLoadingCache.get(LocalCache.java:4821)
at com.google.common.cache.LocalCache$LocalLoadingCache.getUnchecked(LocalCache.java:4827)
at bnq.a(SourceFile:126)
at bhl.a(SourceFile:76)
at bfj.a(SourceFile:52)
at bji.a(SourceFile:122)
at bji.a(SourceFile:312)

-- Item being rendered --
Details:
Item Type: aau@738a815c
Item Aux: 3
Item NBT: {SkullOwner:{Id:"4b7eb6ff-ad34-d6a0-e010-2557cdda33f7",Properties:{textures:[0:{Value:"e3RleHR1cmVzOntTS0lOOnt1cmw6IkFuZHJlYXNrYWwifX19="}]}},display:{Name:"Andy"}}
Item Foil: false
Stacktrace:
at bji.b(SourceFile:348)
at avp.a(GuiIngame.java:1059)
at avp.a(GuiIngame.java:378)
at avp.a(GuiIngame.java:154)

-- Affected level --
Details:
Level name: MpServer
All players: 1 total; [bex['Andreaskal'/761, l='MpServer', x=66,98, y=71,50, z=307,14]]
Chunk stats: MultiplayerChunkCache: 5, 5
Level seed: 0
Level generator: ID 00 - default, ver 1. Features enabled: false
Level generator options:
Level spawn location: 73,00,68,00,289,00 - World: (73,68,289), Chunk: (at 9,4,1 in 4,18; contains blocks 64,0,288 to 79,255,303), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
Level time: 4513350 game time, 4735100 day time
Level dimension: 0
Level storage version: 0x00000 - Unknown?
Level weather: Rain time: 0 (now: false), thunder time: 0 (now: false)
Level game mode: Game mode: creative (ID 1). Hardcore: false. Cheats: false
Forced entities: ~~ERROR~~ ClassCastException: zy cannot be cast to java.lang.String
Retry entities: 0 total; []
Server brand: Spigot
Server type: Non-integrated multiplayer server
Stacktrace:
at bdc.a(WorldClient.java:401)
at avf.b(SourceFile:2296)
at avf.a(SourceFile:334)
at net.minecraft.client.main.Main.main(SourceFile:124)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:483)
at net.minecraft.launchwrapper.Launch.launch(Launch.java:131)
at net.minecraft.launchwrapper.Launch.main(Launch.java:27)

-- System Details --
Details:
Minecraft Version: 1.8.3
Operating System: Windows 8.1 (amd64) version 6.3
CPU: 4x Intel(R) Core(TM) i3-3110M CPU @ 2.40GHz
Java Version: 1.8.0_25, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 280541952 bytes (267 MB) / 535236608 bytes (510 MB) up to 1060372480 bytes (1011 MB)
JVM Flags: 6 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx1G -XX:+UseConcMarkSweepGC -XX:+CMSIncrementalMode -XX:-UseAdaptiveSizePolicy -Xmn128M
IntCache: cache: 0, tcache: 0, allocated: 13, tallocated: 95
Launched Version: 1.8.3-OptiFine_HD_U_D3
LWJGL: 2.9.4
OpenGL: Intel(R) HD Graphics 4000 GL version 4.0.0 - Build 10.18.10.3958, Intel
GL Caps: Using GL 1.3 multitexturing.
Using GL 1.3 texture combiners.
Using framebuffer objects because OpenGL 3.0 is supported and separate blending is supported.
Shaders are available because OpenGL 2.1 is supported.
VBOs are available because OpenGL 1.5 is supported.

Using VBOs: No
Is Modded: Very likely; Jar signature invalidated
Type: Client (map_client.txt)
Resource Packs: []
Current Language: English (US)
Profiler Position: N/A (disabled)

My IGN is Andreaskal PLEASE HELP!!!