Help me as much as you can with paternity

Went to the doctors today and asked him how long sperm can survive in a woman’s body and he said, up to six days well...

I conceived on the 28th

The doctor found out with the ultrasound

I had sex the 25th the day I was ovulating the highest and the guy came inside me

I also had sex with that guy on the 21st he pulled out, and another guy the 22,23rd

He pulled out and also didn’t cum some of the times we had sex

I know this sounds bad.. I was sleeping with my ex and a new guy at the same time for about a year but that’s my business

The question I have is the 21st-23rd

I Couldn’t of conceived considering sperm doesn’t live past six days and the 28th is the exact day it happened

Or is there still a chance?

On the 25th when he did that though... I immediately just knew I got pregnant is that a thing?

Also is the 25th seem like the most accurate day I got pregnant of all four

I am taking a paternity test but waiting till after she’s born I just don’t have to feel super worried about it this whole time

And or look like a fool for telling people the guy is guy number two