Q.W.
My son was an extremely sensitive kid, to things that touched him. Some children are really hyper-sensitive to touch, although they don't know it or cannot express it at this young age. What helped us was toning down any other sensory experiences that were going on at the same time - music, food, visual, etc, and also letting him shop for clothing. I didn't care if he wore the same three shirts every week, because I can wash them, and he found things that didn't irritate him. Sometimes it was a tag, sometimes it was a synthetic fabric, sometimes he could "feel the colors!" So we did a few short shopping trips at some secondhand stores, where everything is a little softer because it's been worn before. You might also try switching laundry detergents, because that may be irritating but you might not know it. I still use Dreft or Baby Ivory for my son's clothes, so there's no perfumes or fabric softeners to irritate him.
I also had "naked time" where it was a designated time to be naked, sort of like an activity. He is five now and doesn't have any more issues (they stopped around three) but he still is very particular about clothing, and can only wear socks that are seamless, and a few quirky things. But he was allowed to choose his clothing, and change it when he wanted to, and we eventually got over the struggles. Patience is definitely helpful, but it will subside. Good Luck!