Am I pregnant?

Hi, so this is really stupid, but I have severe anxiety and can't believe anything and I've been wanting to talk to someone about it. Anyways, so the 24th of December my boyfriend and I tried to have sex, but I'm a virgin so I told him to stop as soon as he tried cause it hurt so bad, and we didn't use protection.. but he barely stuck it in and it was literally for 5 seconds. And a couple weeks later I was super dizzy, but it's nothing new cause I've always had dizzy spells and I told my friend and she was like "you're probably pregnant" in a joking way. And well, that messed me all up. So I of course started having a panic attack and everything for like 3 weeks and I started reading stuff on the internet and it just made everything worse, I've been having my period when I'm suppose to have it, like in January I had my period for 6 days which is normal for me, and then in February I had my period for 8 days, and then I'm currently on my period and this is the 6th day. But last month and this month, my period was early. And my period has been super heavy, which I normal. I've also taken MULTIPLE home pregnancy test, different brands too, and they've all came back negative(9 negative pregnancy text btw), but I literally can't believe anything. The only symptoms I'm having is sick to my stomach, lower back pain, and fatigue. But I started this new medicine near the beginning of January and one of the symptoms is nausea and it's one of the most common symptoms. And I've always stayed super tired from what I remember, I can't remember things well because of mental disorders. And from what I remember, my backs always hurt. But we also recently had sex I think a week ago for two nights in a row, but we used protection so yeah. So if y'all could like, voice your opinions or whatever that would be great, my boyfriend is trying to calm me down but I just don't believe him.