What Do Small Red Rashes On Body Indicate?

I have a blood type rash all over my body, more focused on my feet and inner elbow crease. It looks like a hickey type rash. I also have a lump in my leg near my groin and in my armpit. I feel under the weather constantly and so tired. My entire body itches more so at night. I am constantly at the doctors and gettin no answers and not getting better. What is wrong with me?