What Causes Rash On Thigh That Hurts Upon Applying Pressure?

I have a very small rash at the top of my thigh, it hurts if it is pressed on and the rash does not go away with the glass test. I am showing no other symptoms of meningitis so was wandering if it could be something else? I cannot remember bruising my leg the only thing I can think of is maybe it could be a heat rash as I cycle most places. However this has never happened before and is not present anywhere else. Can you help?