Advice please

Okay so I just had sex for the first time on Tuesday. I'm not on birth control but we used a condom. I checked the condom for leaks and beaks after and I didn't see any. And today I have been feeling subpar. Like I threw up earlier and I feel super dizzy and stuff. I'm supposed to start my period on the 1st. So anything that could put my mind at ease? Other then a test. Thanks!