Hello, Thanks for writing to us. You did sex just after period over and there is NO chance of pregnancy in this case. Pregnancy depends on proper timing of unprotected sexual intercourse with ejaculation inside vagina during fertile period or ovulation day. Other days are quite SAFE. Brown discharge or stuffs may be due to old blood, endometrial tissue, hormonal imbalance, mental stress/ upset, irregular diet habit, vaginal or pelvic infection etc. I suggest you to maintain genital hygiene, urinate each time before and after sex. Practice safe sex in future also. Good luck.