So I just had sex yesterday with my boyfriend and he was sucking my boobs kind of like giving me a hickey and it felt nice so he kept going for a while , it was good and we had sex too without protection but he never ejaculated afterwards so I'm pretty sure im ok . but it's been like 1 or 2 days now and my nipple have a burning sensation to them and only my nipples are sore , not my breast just nipples ! what could it be ?! please help!!!!