Pregnant? or whats wrong.?

Since i was child ive always had fears that i was pregnant. even when my period was late for 1 day. I was scared even if I knew taht it wasnt possible. I still had panics. My period has always been a burden. it may be late for a week, for 2 weeks; Last months i was trying to lose weight so i was fasting then began eating. and during last month my period was late for 2 weeks. Then I bled.. but it was kind of different bleeding. Like on the first day, there was really little amount of blood. on second as well, more than on first but less than usual. and like this during 3 more days. Then it seized. I thought it was fine and it was my period. but then. my breasts. They began hurting alot. I have feeling of vomiting in the mornings ( well sometimes i had it before as well), i feel tired. I eat alot and gained weight again. (well it can be normal because last after i fasted, i started eating alot and gained weight fast again).And I feel strange feeling in my tummy. Like ee.. feeling of fullness.. and like my intestines are in atrophy.This could be because i was drinking like 10 11 tablets of Senade. To not to let absorb eaten food. But something that scares me the most is this breast hurting. Ive never had it that long. Im 18 and studying medicine. I know its not possible.. that I could be pregnant. But these fears and panics still dont leave me. Im virgin. Ive never had sex. but I was in such despair that I even bought home test. and it was ofc negative. My period should come in 20 days.and im so scared. I know logically it cant be. but why do my breasts hurt? Why do i have symptoms like this? Please dont start talking about virgin Mary and etc. and Tell me have you had situation like this?