In that case, maybe there's a risk... Was the sperm transfered to your vagina through a finger underwater? Cause I think the water could damage the sperm that way. But here's something I usually do when I have a question about sexual stuff: there's a live chat on Planned Parenthood's website where you can get more accurate answers. They're really nice! I'm really sorry if I can't give you a better answer, but you can really trust them to help you out
Hi! What do you mean by contact with semen underwater? If you didnt have sex underwater, with someone ejaculating inside of you, then there's nothing to worry about. What people mean by getting pregnant without having sex is when someone ejaculates in your vulva or near the vagina openning. Or if sperm gets in your vagina by something like fingering with sperm on your fingers.