Does The Fertilization Of Egg Takes Place During Ovulation?

Me and my ex boyfriend had sex on nov 20th with a condom,when he was about to ejaculate he pulled out and took the condom on and ejaculated on my lower stomach and a lil bit slid down near my vagina area,I dont think he could be the father but he does,could he be? That next week around nov 25th or 26th I had sex with some one else wich was unprotected but I don not remember if he ejaculated in me or not,I dont think he did,But i think he is the father. I've heard that ovulation takes 6-12 days and my doc told me that the egg ovulated on dec 2 and I was on my period from the 1st through 5 or 6th then had another period at then end of dec til jan 1st? Could u help me