LAst week I discovered 3 VERY Big and Itchy knots on the back side of my neck.. thought they were maybe an insect bite. They are Sore and Itchy!! they went away after a few days. Last night I found another big knot on my elbow and one on my arm. Any suggestions on what could be causing this or what it is??? Allergic reaction to something maybe??? this has been going on for a week now.....