Could you clarify who is who? You said three things in your first sentence:
"i have a boyfriend but on nobember 26 o 27 2016 cant remember well what day we had an argument"
"i had unprotected sex with a guy dats not my husband"
"i wemt back with my boyfriend 28 and had unprotected sex with him"
Are you saying you have a boyfriend, a husband, and "a guy" who is "not your husband"?
Then, you had a period December 9. After that you had sex with your husband. It sounds like he is the most likely candidate for dad, because of your period. Unless you had sex with someone else in December. What is your estimated due date, and did you get it from an ultrasound?