Who could be the possible father. Guy?

I'm not proud of it, but My period started October 17 I've did a lot of conception calculations and I would have ovulated on the 31st . I had sex with one guy on the 30th unprotected he wasn't sure if he ejaculated in me . Though when I left he said he came to fast but I don't remember seeing any white substance anywhere so we both believe it went in me. I took a test the next day it said negative . So I moved on , then on November 3 ,4 days later I had sex with someone else The second guy is pretty sure he didn't nut inside of me , he said he's pretty sure he pulled out way before he nutted because afterwards he nutted on the floor .but there's still that chance of possibility he could be the father right? Who is most likely to be the dad ? Most of the fertility calculators say I was very fertile from october 26-31 and ovulated on 31st only one or too said I ovulated on 31st but still fertile all the way up to the 4th . . The possible father would most likely be the first guy ?