Pimple like itchy spot mostly on arms and legs but also other areas

[Dan92_1]

So I have been getting spots for about 8-9 weeks.  They tend to itch, at different times of the day, then get really itchy, the spot then gets big and raised, and after an hour or two goes down to a smaller red spot almost not visible usually within a couple hours or sometimes 48 hours.   Then they are gone.  When I first notice them, its really itchy, the middle of the area is white, and surrounding it is red.  When I take pictures of them, they look like a pimple with a white head.  Sometimes a get a group of 2-4, sometimes just one.  Some days I will notice up to 6-8 new areas, that can be both arms and both legs the same day.  Some days not much.  They do vary from smaller spots that come and go to much larger spots that come and go.  I have seen my Dr. and Dermatologist, Dr. said it didn't look like insect bites but wasn't sure.  My Dermatologist says not insect bites, but I do have clear Eczema in some areas so he thinks that is causing these bumps to come and go.  I just started treatment for Eczema today, but I feel like that doesn't explain these bumps, the flaky skin that is Eczema really doesn't bother me, but is it possible it can cause these other reactions?  They are completely different symptoms, and if not what else could it be?  Everything I have looked up does not seem like a fit.  I have gotten allergy tested in the past, and am allergic to a wide variety of things, so was thinking of going back to allergist to see if we can figure this out, its getting extremely frustrating.  Sorry about the length of this post.