About 2 weeks or more ago, I spent sometime with a male friend and even though we didn't have intercourse, we did do other stuff that left me with some of his sperm in my hand. After I went home, I masturbated with the same hand without washing it and now i'm scared that i might be pregnant. I know it's very unlikely however after that day, ive been having a brown string-like discharge, mood swings and pain (no too strong) in my lower abdomen. Do you think I could be pregnant? or Could there be something wrong with me?