Is it normal that i get angry for no reason

You just had a baby! Your hormones will calm down in about a year. Thats just how it works. However, if it's affecting your duties as a mother, I would definitely talk to my doctor about getting some help. Nothing to be ashamed of.

stress?

You yourself seem to be associating childbirth with your anger issues. If that's it, the solution is simple. You suspect the reason for your anger and can maybe deal with it, either yourself or with someone else. I hope it's as simple as that. If not, you need to dig deeper either with yourself or with someone else.

Post natal depression.

Just don't harm the children, but U should see a shrink about it.