Nauseous

So I’m on birth control(the pill) and I take it every day at the same time. If not then usually an hour late. I have a serious bf and we have sex about 1-2 times a week. We never use condoms but he pulls out. I’m supposed to get my period either today or tomorrow but this morning I woke up so nauseous. I don’t know if it’s because i have stressed myself out or what but as soon as I woke up I did not feel good. Please help