Hello Im Trying To Figure Out The Possibility Of 2

Hello Im trying to figure out the possibility of 2 father’s. My LMP was Feb 12 and my cycles are very regular always 28 days and period lasts 6 days. I had a one night stand on the first day of my period February 12 then my exbf who lives in a different city came and we had unprotected sex on February 13 and almost everyday until March 3 when he went back home. My ultrasound are saying that baby is due November 19 so it’s according to my LMP. I think it’s guy 2 but am stressed because I’ve heard that sperm can live in ideal conditions for 7 days but wouldn’t being on my period not be an ideal condition? I am back together with guy 2 and he is very excited to have a baby he proposed to me 2 days ago. Please tell me what you think?