Confused about my conceived date

So this may be a long shot..

As usual like I do every month I log my period from the first day it started to the end date.

I was out of town for awhile and I started seeing a guy, well I started my period on April 18th we had sex April 19th and he cummed in me. After that we had sex when I got off my period and the last day I seen him was Sunday April 28th. But he didn’t cum in me anymore after my period.

I come home and me and my ex got back together but we didn’t have sex until May 4h.

It says on my calendar that my ovulation date was May 3rd.

Well I am 5 weeks & 2 days pregnant.

When I do the conception date calendars it says that I conceived on May 2nd. And my due date is Jan 23, 2020. But the guy out of town didn’t cum in me anymore. And my ex did on May 4th. I am a bit confused on how this goes. I’ve never been pregnant before I was told that I couldn’t have kids.

Can someone please help me out. My mind is just going in circles around this.