Just to add my experience,
I never had any clothes aversions or any of these symptoms as a child. No allergies, no sensory issues, really normal.
I had nothing like this as a child either, my brother had loads of allerigies, and excema.
I have an odd thing where I have to keep my hands in my pockets and look away, when someone stands in front of me wearing clothes of certain materials, the desire to see what it feels like is almost overwhelming.
on the shorts/pants in bed thing, OMG I have 2 holey, thread bear, favourite pairs of shorts that I love. The waist band is in bits, but they are so comfy, and nothing else comes close. They're my sleep like a baby shorts.
I would be mortified if they ever had to appear in public though!
Or perhaps we should start a pants thread, to go along with the sock thread, we all send photo's of our favourite most comfy pants.
If that don't start a wave of concern nothing will, and its probably weird and unsightly enough to get publicity.