funny story well at least it was for my husband of 6 years.
my hunny and i was watching a movie in bed and i ask him to give me a head rub. so he rubs his finger tip through my head and i made him stop cause my hair has been itching a lot and he made me more itchy.as im rubbing my hair i find a BIG BALD SPOT. i got up and ran to my bath room to see what was going on and my husband dont know whats going on is freaking out thing it was something with the baby. im crying and screaming and he is trying to calm me down so i dont scare my other kids and i show him the spot. he said i that it. and starts to chuckel. i got a half doller coin and put it to my spot and it fit. i dont know how this happend i dont know why this happed but all i know is that im four months pregnate with my 4th child (hope its a boy i have 3 girls) and i found a bald spot. what can i do while im pregnate.
that happened to me when i was 17...exactly as you've described it, but sans pregnancy. its a condition called alopecia areata, and my doctor told me that it is triggered by stress, mainly in young women. it's fairly rare, but your hair will grow back. all you can do is wait. it only happened to me once. pretty embarrassing, but other than that, not so bad. supposedly its an auto immune thing.
i would see your doctor if you're concerned...but it's nothing to worry about...honestly.