Hair falling out??

Has anyone hair fell out after giving birth or during?

After my son (third child) my hair has fallen out way too much. I mean not just in the shower or when I brush my hair. I could just be sitting down and when I get up I would have strands of hair all over the place. My (now) husband says there's traces of my hair everywhere. You can not noticably see where my hair has fallen out because my hair is about 2 1/2 long and very thick. But I can notice it.

Backstory...

I was going through a bad divorce my last trimester up to when my son was about 4 months old. So I was super stressed out.

Could that be why? Also what can I use to grow it back fast for an affordable price?