is this sketchy?

So theres a new guy iv been seeing i like him he's really sweet etc but he automatically thinks we are in a serious relationship & i feel like it might be because we had sex on the first date. Second thing is that apparently he wasnt listening when i said im on birth control & he came in me a few times... im ok with it but what I don't understand is did he think that i was just gonna get pregnant & he be that chill with it (since he thought i wasnt on anything).