Pregnancy Scare

Hello! So about a month ago I went to the OBGYN because i couldn’t feel my IUD strings. They did an ultrasound and said that my strings went up but my IUD is still in place. The other day me and my SO had sex with no condom and he pulled out before he came. He told me he had peed earlier that day so I don’t think that there could be sperm in his precum, but one thing is that he precums a lot. Should I be worried about pregnancy if I have hormonal IUD with strings up but still in place?