HELP!! Pregnant? PLEASE RESPOND

So me and my bf had sex and we used protection but there was one time he was playing too much and slid in ONCE without the condom on but he wasn't all the way hard and from examining before hand there didn't appear to be any pre-cum. My period was like 4 days late and then I bled heavy for like 2 days and the other two it was like I wasn't even bleeding. There was no cramping or anything. I'd put in a tampon and it would be bloody on one half and not the other. Could this be spotting? Could I be pregnant? Mind you my periods usually last like 5-7 days and are usually heavy with lots of cramping, I will say though, last time it was only about 3-4 days. Also I did just start having sex in August and it's only happened 3 times since then . Could this just be my body adjusting? Please HELP