Am i pregnant or do i have a virus?

to get it straight i was with a guy and he d from four play i dont know if pre-ejaculation got near my but we didnt have cause im a virgin. This happened after my period was over, it actually ended that day, which was March 4th. Then the week of March 15th i started having headaches, fevers i had a spotty stomach rash and dry throat. So i went to the doctors and gave them a blood test urine exam and throat exam, also that day i got my period it came 8 days early though and was very light and lasted 2 days. The doctors said i didnt have mono or anything but maybe a virus.The symptoms all went away by around March 21st. I woke up the next day and my stomach felt very bloated ecspecially my belly on, it feels squishy and hard around my lower abdomen. i do have loss of appetite and have lost weight, my arent swollen and i dont have morning sickness. I do have diarreah after i eat sometimes though and just my stomach always feeling bloated. This has lasted about 5 days, its scaring me cause its not going away. Im 18 by the way not planning this, so am i pregnant or do i have some kind of virus? Would the doctors who looked at my blood and urine tests have known to look for pregnancy and not mono which they thought i had?