If it is any antidote to feeling kind of foolish for asking, you're not the first person to write into this site asking a similar question. Some guys get the notion that their natural juices are so mighty that simple proximity to them makes all women in danger. To keep from being one of those guys, do get your facts, sort out your anxieties, and keep reality in mind.
As Curfew says, for a pregnancy to be possible, the semen has to be put into the vagina by direct contact or has to be deposited right into the secretions at the mouth of the vagina. (In that latter scenario, the vaginal secretions would have to be thick enough to protect the sperm from the air. It's not a common way to get pregnant.) Contact with air kills sperm. Semen can't crawl around a woman's body. Sperm is not going to survive more than maybe a few seconds on bedclothes. The chemicals in a Baby Wipe will also likely kill it.
If your "overly paranoid" question is in fact more along the lines of "What would I do if the woman I just went to bed with got pregnant?!?" the way to deal with that worry is, every single time you have a sexual encounter, use condoms. It's the responsible thing to do anyway, protecting against an unwanted pregnancy and the threat of STDs.
Good luck in the future. You didn't get her pregnant.
Any method apart from putting a penis, without a condom on, inside a vagina is NOT going to result an any realistic chance of pregnancy. Semen on surfaces, including bed sheets and baby wipes, cannot make its way up the vaginal canal - sperm don't have that level of motility. Many people try for a significant amount of time to achieve pregnancy via having unprotected intercourse before they are successful. It's not going to happen by some astronomically impossible chance like the circumstances you mention.