I feel sick

I'm 18. So Saturday night my boyfriend put half of his penis in me WITHOUT a condom. Before this, we have sex four times but WITH a condom. He has never ejaculated inside me. We both checked and he was dry both times. He just put in it twice and that's it. He is confident that I am not pregnant, since I have been on birth control pills for about four months. I took my last active pill tonight and I start my week of sugar pills tomorrow night. I have had menstrual cramps all week, some back pain, kind of sore breasts(but that could be from going to the gym everyday), and I am very emotional today as well. This all started a day or two after he stuck it in twice without the condom. My friends tell me to relax, that I am not pregnant and perfectly fine. They all don't use condoms with the pill and their boyfriends ejaculate inside of them. They have never been pregnant. I always use condoms and take my pill at 6 pm everyday. I've never missed a pill. Can someone please ease my mind? Am I having normal PMS symptoms? Or could I be pregnant?