I'm on the pill and my period isn't here yet is this normal?? 😫

So I've had sex twice this month and neither of those times we didn't wear a condom one time was after my period finished and other other was first day of me ovulating and he didn't cum in me but my period is now 3 days late I've already taken 3 sugar pills and have 1 more to go until I go back to my pink tablets and I'm really scared I don't know what to do I've been feeling sick in the gut for a good 3 weeks now and I'm only 17 so I hope I'm not pregnant my parents are really strict and would actually kill me, I think I'm just stressing myself out but I honestly don't know what to do is it normal for my period to be 3 days late on the pill??? Usually my period is accurate and on time.