pregnant and confused because I don't know who is the dad of my baby

My current partner and I split up on 7th of August, I had unprotected sex on the 8th of August and again on the 9th of august.we then got back together on the 10th of August and had unprotected sex for about 4 days straight. I have recently found out that I am pregnant and due the baby around the 8th of may.I was told the best way to get the conception date is to take 38 weeks off your due date and that took me back to August 16th. Is my boyfriend my babies dad? Please help I am so confused