Minecraft keeps crashing with exit code 9

The same thing as yesterday and the game just keeps crashing.
Also, the two times that I've been able to play the game, it had a lot of lag and I couldn't do a 360 with my mouse. I would stop moving side to side when my mouse hit the sides of my screen. I couldn't look down either. I don't know if this is normal and I would really like some help. I haven't been able to play Minecraft properly in a year and I just miss it.