I'm 19 years old and slept with my fiancée about 2 or three weeks ago. My period came on the 12th of last month went off like the 21st. Then I started having symptoms and just wanting to sleep. I really haven't had no type of appetite since then but I did gain about three pounds. Then I saw brown stuff in my underwear and didn't know what it was but thought it was normal but the day after my period came on again but this time I lost tissue and it was heavy. I'm scared there's a chance I could be pregnant but I'm not sure. Could I be?

Yes, if you had sex, you could be pregnant. Your next step is a pregnancy test, either at home, or in a doctor's office.