Pregnancy Scare? (Probably just over paranoid)

So my cycle started on March 2nd, I went to my boyfriends house on the 10th (it said 7% of pregnancy even though my fertility window doesn't start till the 13th). We had sex and used a condom, but he put it on backwards at first. He swears up and down that there was no pre cum on it but I'm still super worried. I had an ovarian cyst that burst on the 18th and went to the ER and they had to do a blood, urine, and transvaginal ultrasound. They would've said if I was right? I usually start around the 29-33 day of my cycle.  But I'm not having any symptoms.