that is known as spotting or implantation bleeding. you could be pregnant. i would suggest waiting two the three weeks since the day you had unprotected sex, then it should give you an accurate result! best of luck
If the guy cums inside in, your vagina. Then theres a chance specially if it happened in your ovulation period. Theres chance that youre not pregnant if it happened 7-days before or after of your next predicted period.