Suggest Treatment For Swelling & Rashes On Elbow

My left elbow, initially tender as if I banged it against something (a week ago) though I don't recall any incedent now has become swollen and quite warm to the touch, swelling radiates from my elbow up my forearm. it feels as if there is liquid inside. An hour ago I noticed an odd rash developing on the inside of my elbow (crux) red, sort of lines, not ithy