Hi , My Name's Adrianna Im 16 & I Had

Hi , My name's Adrianna im 16 & I had unprotected sex on the 28th of August , I got my period the day after intercourse & it lasted for 5 days , it usually lasts up to 7 but The guy that I had sex with ejaculated in me twice on two rounds of sex in a day. I don't know if its possible I can get pregnant on my period if i have irregular cycles. I don't know if its to early but right after intercourse that day I felt different than the other times I had sex because this time my stomach felt quite different like it was heavy & it still feels odd right now. I lost my appetite , I have shortness of breath , & Im tired frequently. I have to change my bra size as well cause my breasts are growing. Is it possible to feel symptoms after 6 days of unprotected sex? do you think I could become pregnant?