I haven't been able to play mine craft for 3 days now because it says my game has crashed.

Put the summary of the bug you're having here

What I expected to happen was...:
Describe what you thought should happen here
I should have been able to open mine craft
What actually happened was...:
Describe what happened here
When i opened it is said Mojang then it brought me back to a page that says uhoh looks like your game has crashed.
Steps to Reproduce:
1. Put a step by step guide on how to trigger the bug here
2. ...?
3. ...?