Could I be Pregnant?

My boyfriend and I ALWAYS use a condom every time we have sex & I take my birth control at the exact time every day. Last month I got my period a few days after we had sex but here recently I have been feeling super paranoid that I may be pregnant. I don't really have any symptoms except nausea occasionally. Have any of y'all ever experienced this or have any pointers? I keep trying to convince myself that there's no way I could be but I'm still scared! Help!