Hi. I have a rash or hives that are on my legs, arms, stomach , back, and chest . My stomach and back are completely covered with tiny bumps. There are also many that are larger in size, fewer in number and pimple like in appearance. The larger ones seem to be mainly on my arms, legs, and chest. Not much itch overall. I have had this for 3 days and have taken Benadryl and over the counter cortisone cream with no improvement. Do I need to go to a dermatologist or just hang in there for a few more days?