Chew hair

This is weird but ever since my like third trimester started I’ve been chewing hair. Like when I brush my hair I’ll pull the hairs that are on my brush and chew them and bite and then I’ll throw it away I won’t eat it. Or I’ll run my fingers through my hair and if hair falls out I’ll do the same chew n bite it n throw it away.. this just started happening during my pregnancy never done this before. My iron and everything else is good so idk what’s wrong.