Trying to convince

am 19, I had a period from 9/8/18- 9/12/18. I had sex 9/13 and bled for a little. 9/15 I had sex and had brow spotting the best day 9/17, 9/18 9/22 9/23 9/24 9/25 I had sex my ovulation I be live was on the 17th because I took ov test my period should come 10/4 but could I have gotten pregnant yet.