Ugh help

on april 28th 2018 me and my bf broke up and i went to a bestfriends house and got drunk and it got kinda nasty we had a threesome then on may 17th i found out i was pregnant and that i was almost 7 weeks pregnant!;/ my fiance family is telling him the baby isnt his and blah blah (i did the threesome at the end of April) my first ultrasound said my last period was april 2nd and on may 17th i was already 6 weeks and 4 days... I just want your mommas options cause their stressing me tf out.....