Health

Hi, so I've been with my boyfriend for two years now and we've been fooling around for a few months. Just touching and recently started to try oral (we've done that about three times now). I'm also a college student and just finished with the stressful exams for the semester. Well since about March my periods have been really weird. I've hardly ever been late on my period and never missed it, but since March I've had symptoms that I don't usually have and it's just been getting weirder. I was a few days late in March and I started thinking I was pregnant (which couldn't have been possible because no penetrative sex, and none of his sperm anywhere near my vagina) and really started freaking out because that was the very first time that had happened. I thought it might have just been stress with midterms and that it would calm down in April. However it happened again and I started spotting before my period which I have never done before and I have no idea if that's normal. I've tried looking it up but all that comes up is pregnancy, but I'm not pregnant. Then this month I was supposed to start yesterday, but I'm late again and my symptoms are irregular again. I've hardly cramped (which I'm usually doubled over from cramps), and I've been super nauseous but hungry at the same time which I'm not, usually. It's normally one of the other. I don't know if I'm just freaking out over nothing or what, I'm not sure if it's because of stress or because my boyfriend and I have been fooling around (but we have been months before this started) or something else. Does anyone have any thoughts, advice, or have gone through the same thing?