What Causes Brown Vaginal Discharge And Swollen Breasts?

hi, i recently had sex just after my periods got over and it was unprotected sex. i did take a contraceptive pill. but after now 21 days suddenly a brown kind of sticky thing is coming out of my vagina. and from past a week i am feeling sudden tiredness, restlessness and i am kind of sleeping most of the time, and my breast are swollen and numb, i have head aches, become very sensitive to smell, and there is a sensation of vomiting and kind of black out some times, and a little lower abdominal pain. i just need to know am i pregnant or what is it.