I Have A "bite" On My Right Arm Between Bicep

I have a "bite" on my right arm between bicep and tricep, and it looks feels and itches like a mosquito bite. It has been there for 6 months or more. it has a firmness to it like a mosquito bite, and itches more if i scratch it. It certainly seems allergy, or histamine related if that makes sense, but I have no idea if it is possible to have that effect from a mosquito or similar for such a permanent amount of time.