What Are The Symptoms Of Eczema?

I am 52 years old, a female. I am 5'2" and weigh about 180 lbs. I have diabetes, and take medication for it and for high blood pressure. I have had shingles, I have been told that I have a poor immune system, I have a skin problem that was told was psoriasis but then was told it was an ecema not psoriasis. I have allergies all year round and take medication for it. So my problem: This is going to sound bizarre but here goes...a few years ago in May/June I began to notice - especially while lying in bed, trying to sleep for the night, that my upper arms (first one arm and then later the other arm), starting on the side of my armpit and then gradually over the course of a month, down to the center of my upper arms, I would get an itching, stinging pain that when I would scratch and eventually put compressess on would not go away. Sometimes I will put ice on my arms and that worked (sometimes) until the ice melted and my skin was no longer cold. I do notice it sometimes during the day but always notice it at night. It has been occurring for a few years and always starts in about May/June and dwindles in about Nov. It has started now and of course I can't sleep...help!!!