After Launching minecraft goes to 'Not Responding'

Minecraft Crash Report ----
// But it works on my machine.

Time: 28/10/14 1:54 PM
Description: Initializing game

java.lang.OutOfMemoryError: Java heap space
at cue.a(SourceFile:230)
at cua.b(SourceFile:130)
at cua.a(SourceFile:77)
at cxh.j(SourceFile:553)
at cxh.a(SourceFile:139)
at cxk.a(SourceFile:23)
at cvt.a(SourceFile:99)
at bsu.aj(SourceFile:437)
at bsu.a(SourceFile:299)
at net.minecraft.client.main.Main.main(SourceFile:120)

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

– Head –
Stacktrace:
at cue.a(SourceFile:230)
at cua.b(SourceFile:130)
at cua.a(SourceFile:77)
at cxh.j(SourceFile:553)
at cxh.a(SourceFile:139)
at cxk.a(SourceFile:23)
at cvt.a(SourceFile:99)
at bsu.aj(SourceFile:437)

– Initialization –
Details:
Stacktrace:
at bsu.a(SourceFile:299)
at net.minecraft.client.main.Main.main(SourceFile:120)

– System Details –
Details:
Minecraft Version: 1.8
Operating System: Windows 8.1 (amd64) version 6.3
Java Version: 1.7.0_71, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 1310496 bytes (1 MB) / 1060372480 bytes (1011 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: 0, tallocated: 0
Launched Version: 1.8
LWJGL: 2.9.1
OpenGL: Intel(R) HD Graphics 4600 GL version 4.2.0 - Build 10.18.10.3412, 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: Probably not. Jar signature remains and client brand is untouched.
Type: Client (map_client.txt)
Resource Packs: [Sphax PureBDcraft 512x MC18]
Current Language: English (US)
Profiler Position: N/A (disabled)