I have these issues. Luckily, I think this is one area where exposure therapy works well because there are so many opportunities to employ it, and without as much consequence.
For example, some of my germaphobia has to do with food and eating. It got so bad that I progressed to the point that everything I brought home from the supermarket had to be cleaned or wiped down. One day I realized I had opened, cooked and eaten a can of beans without washing it. (Boxes and bags I would wipe down...cans had to be literally washed with soap and water). This happened with a couple of other items as well. When I didn't get sick from it, It began to lose some of it's power.
For example, your pajamas. Try letting them touch the ground just a little, even it it's just a tiny bit. Or maybe try being just a
little less conscious if your efforts to prevent them from touching the ground or other clothes. Here's a good analogy involving my food OCD: Despite the fact that I need to have total control of how my food is prepared, I still eat out occasionally. I know damn well that my food is being prepared without my supervision. I can't inspect the cookware, or the cleanliness of the plate it's being served on, or the habits of the restaurant staff. But I'm so used to eating out throughout my life that it's like I can put these feelings on hold. I know of no better way to explain it. I don't know if I have some unknown mechanism for turning off these fears when I eat out, but I don't overanalyze it. I don't analyze it at all.
You can apply this to your clothes. Know that there is virtually no way for youth completely control what they come in contact with. This may result in discomfort, but it's the only way you will be able to beat the fear. Little by little, let them touch other clothes. Don't go overboard. If anything, use restraint, but not as much restraint as your OCD forces on you. Progress may be slow, but it's progress nonetheless.
For example, when I first realized I had eaten food from unwashed containers, there was nothing I could do. It was already eaten. Had I known, eating it would have been impossible. But I
didn't know, I
ate it, and I was none the worse for it. Because I didn't know, my OCD didn't know, and I was able to defeat it.
Do you live with someone you can trust to help you with this? Maybe you can ask them to "contaminate" your pajamas
just a little, without you knowing. I'm not talking about bringing them to the laundromat and rubbing them all over some stranger's clothes

, but in tiny little ways that wouldn't drive you insane if you knew. But you won't know. Then have them tell you the next day, or even in a couple days. It might help youth realize how insignificant these fears are compared with what OCD is telling you.