could I be pregnant?

So I'm in my 3rd month of birth control I had my break and a period and I started taking the pill on the correct day however on that day I had unprotected sex he did not cum in my however it's 5 days later and my boobs are really sore under the boob and during sex ive had a bag pain at the bottom of my stomach, I also feel really sick and my stomach feels strange and hurts to touch or press down on... is there a chance in pregnant? Or am I just overthinking. I am 16 so it could just be my boobs growing or something but I just need some help! X