For the itchy rash that is possibly related to the pant's button...it could be a nickel (or other metal) allergy. Try coating the metal that touches the skin with a liberal coat or two of clear finger nail polish and see if that helps. It sounds like a contact dermatitis from the metal or a component in the metal.
also, i haven't done laundry in a very long time, which is embarrassing to mention, but with that aside, could that contribute?
i have the same thing! i don't know if it's related to some jock itch problems i've been having recently but it is driving me crazy. i just noticed them last night, and it seems to have gotten a bit worse since then. then do not itch, they are very tiny and red and seem to be only on my stomach, most are located below my belly button, with a few just above it. i thought it might be hives, but aren't hives more in large patches? looking now, it seems to have spread to my arms, so maybe it could be hives? i have bad anxiety problems so hives seems like it might be the case. any advice would be much appreciated!
oh and its only in one spot.. about 1" x .5"