Sex after baby

So ever since I was pregnant I haven’t had any interest in having sex. While I was pregnant I didn’t have much interest either, unlike the movies where the woman is perceived a a pregger sex maniac that is horny 24/7, I really wasn’t into it. My baby girl is about to be 6 months old and I think we had sex maybe 2 times since she was born and both times it was pretty painful. Being the typical guy always asking if we can have sex, my husband is getting annoying and now assumes something must be wrong with me because I don’t want to have sex. Is this normal? Is it part of postpartum? He is really bothered by it but I honestly could care less....advice please!?!?