Rug Burn On Elbow, Intense Pain And Burning, Bright Red Bump On Elbow And Upper Arm. What Could It Be ?

last night i felt like a had a rug burn on my elbow but since i was in bed i thought nothing of it and went to bed. I woke up and the pain was intense and burning, so I went to look in the mirror and there was a bright red bump on my elbow and another on my upper arm. They were both bright red and painful maybe about the size of a quarter. I thought maybe they were really painful big pimples even though they don't have a white tip so i tried to squeeze the and they turned white, slowly going back to red and burned so bad i had to stop touching them. ( i do have really bad anemia though). A few hours later, i checked it in the mirror again. The bump on the elbow was still the same but the one on the upper arm has two red squiggly lines running up near the armpit but then the lines come together (kind of like a weird triangle were the base is the bump). the bump is still red and burning, its also warm. I live in Massachusetts and we don't have many poisonous insects r spider bites, what could it be?