Put the summary of the bug you're having here

What I expected to happen was...:
I thought I'd logged in and was ready to play.

What actually happened was...:
After selecting my world to play I thought I was ready to play but then 5 seconds into moving around the screen closed and I ended up back at the minecraft launcher.

Steps to Reproduce:
1. Logged into Minecraft
2. After it loads I clicked my saved game to play
3. After that loaded I have about 5 seconds of play before the screen disappears and brings me back to the minecraft launcher screen.