Nipple Piercing Aftercare Tips??

So I just got my nipples pierced! I was told to wear cotton bras that aren’t tight, but I’m really small chested and got used to not wearing any. It just makes me feel really uncomfortable. Any tips for that?

Also what do you girls do when you shower and wash your hair? I don’t want to get any shampoo or other suds on it. I purchased the h2o piercing spray which I heard was really good, and I’ve got my gauzes and cotton tips.