I have been playing on this world for a while now, updated the world from 1.14 to 14.2 with no problems, but today I downloaded 1.14.2 Optifine and it started crashing when I would load chunks. Even with changing off of Optifine it would still randomly crash. 

Not sure what to do, also a point to mention, It crashes very fast when I fly on my elytra.

Crash report:

---- Minecraft Crash Report ----
// My bad.

Time: 6/6/19 9:35 PM
Description: Exception ticking world

java.lang.OutOfMemoryError: Java heap space
at ij.a(SourceFile:64)
at ib.a(SourceFile:438)
at ib.a(SourceFile:81)
at ib.a(SourceFile:438)
at ib.a(SourceFile:81)
at ib.a(SourceFile:438)
at ib.a(SourceFile:81)
at im.a(SourceFile:113)
at im.a(SourceFile:78)
at im.a(SourceFile:74)
at bya.e(SourceFile:53)
at us.g(SourceFile:786)
at us.j(SourceFile:505)
at us$$Lambda$2567/369570908.get(Unknown Source)
at java.util.concurrent.CompletableFuture$AsyncSupply.run(CompletableFuture.java:1582)
at agk.h(ThreadTaskExecutor.java:159)
at agk.p(ThreadTaskExecutor.java:130)
at ve$a.p(SourceFile:507)
at ve.d(SourceFile:236)
at net.minecraft.server.MinecraftServer.aW(SourceFile:708)
at net.minecraft.server.MinecraftServer.p(SourceFile:696)
at agk.c(ThreadTaskExecutor.java:143)
at net.minecraft.server.MinecraftServer.o(SourceFile:681)
at net.minecraft.server.MinecraftServer.run(SourceFile:636)
at java.lang.Thread.run(Thread.java:745)

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

– Head –
Thread: Server thread
Stacktrace:
at ij.a(SourceFile:64)
at ib.a(SourceFile:438)
at ib.a(SourceFile:81)
at ib.a(SourceFile:438)
at ib.a(SourceFile:81)
at ib.a(SourceFile:438)
at ib.a(SourceFile:81)
at im.a(SourceFile:113)
at im.a(SourceFile:78)
at im.a(SourceFile:74)
at bya.e(SourceFile:53)
at us.g(SourceFile:786)
at us.j(SourceFile:505)
at us$$Lambda$2567/369570908.get(Unknown Source)
at java.util.concurrent.CompletableFuture$AsyncSupply.run(CompletableFuture.java:1582)
at agk.h(ThreadTaskExecutor.java:159)
at agk.p(ThreadTaskExecutor.java:130)
at ve$a.p(SourceFile:507)
at ve.d(SourceFile:236)
at net.minecraft.server.MinecraftServer.aW(SourceFile:708)

– Affected level –
Details:
Level name: EndGame
All players: 1 total; [vh['Mcswagens18'/149, l='EndGame', x=1289.33, y=82.77, z=-138.00]]
Chunk stats: ServerChunkCache: 4424
Level seed: -583644741394684071
Level generator: ID 00 - default, ver 1. Features enabled: true
Level generator options: {}
Level spawn location: World: (-80,63,167), Chunk: (at 0,3,7 in -5,10; contains blocks -80,0,160 to -65,255,175), Region: (-1,0; contains chunks -32,0 to -1,31, blocks -512,0,0 to -1,255,511)
Level time: 3727415 game time, 4232959 day time
Level dimension: 0
Level storage version: 0x04ABD - Anvil
Level weather: Rain time: 29590 (now: false), thunder time: 49554 (now: false)
Level game mode: Game mode: survival (ID 0). Hardcore: false. Cheats: false
Stacktrace:
at net.minecraft.server.MinecraftServer.b(SourceFile:830)
at net.minecraft.server.MinecraftServer.a(SourceFile:764)
at dxk.a(IntegratedServer.java:159)
at net.minecraft.server.MinecraftServer.run(SourceFile:632)
at java.lang.Thread.run(Thread.java:745)

– System Details –
Details:
Minecraft Version: 1.14.2
Operating System: Windows 10 (amd64) version 10.0
Java Version: 1.8.0_51, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 907479600 bytes (865 MB) / 1308622848 bytes (1248 MB) up to 8589934592 bytes (8192 MB)
JVM Flags: 9 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xss1M -Xmx8G -XX:+UnlockExperimentalVMOptions -XX:+UseG1GC -XX:G1NewSizePercent=20 -XX:G1ReservePercent=20 -XX:MaxGCPauseMillis=50 -XX:G1HeapRegionSize=32M
Player Count: 1 / 8; [vh['Mcswagens18'/149, l='EndGame', x=1289.33, y=82.77, z=-138.00]]
Data Packs: vanilla
Type: Integrated Server (map_client.txt)
Is Modded: Very likely; Jar signature invalidated