Help need answers

I was on my period from September 1st-8th, my boyfriend and I were broken up and I had sex September 5th with my ex. I had an IUD in place at the time of sex.. but then I removed my IUD 16 hrs later, then like the next day I got back with my boyfriend and started having sex with him regularly. Now I’m pregnant, don’t know how far along but I’m testing positive on FRER, the digital as well. And i’ve tested positive on the cheap tests as well. I don’t know how long my cycles are, and I have irregular periods.

What are the chances of me getting pregnant, while on my period, with an IUD in place, and then I removed it 16 hours later.. I don’t want my ex to be the dad.

Any answers or guesses would help me a lot. I just want some kind of answer that doctors won’t give me.

I had planned parenthood say I’m 4 weeks and 3 days and FPA women’s health said I was only 2-3 weeks and on the 19th did a transvaginal ultrasound and said there was nothing there... I’m rather confused.

Heeeelp