Unprotected intercourse April 20th-25th (one time, can’t remeber exact date). He did not ejaculate in me. IUD removal April 27th. Started bleeding April 29th-May 1st or 2nd. Fairly light but enough to fill a tampon. Started bleeding again on May 5th-8th, which was heavy for the first two days then by the 8th, very light and gone. I don’t remember my last period from before this bleed. I always had normal cycles while having the IUD which was four years. I’m assuming the second bleed was my period but I don’t necessarily know for sure. I was also having unprotected sex with another man during this time, all through April and May. He did ejacluate in me multiple times throughout both months. I tested for pregnancy all through the month of May, I got a positive test I believe on May 29th. My due date is February 9, 2019. When I use a due date calculator it says possible days of conception is May 19th... which I assume would be the second man. BUT, how common is it to get a positive that soon after conceiving on the 19th... I know you can bleed and still be pregnant, but if it would be the first mans baby, wouldn’t I be much further along? I had an ultrasound on 6/15/18 which the baby measured 5w6d. I had went in a week prior and only a yolk sac could be found at the time. Are ultrasounds full proof that early on figuring out possible conception?