What Does An Itchy Lump On The Jaw Bone Indicate?

I am an 81 Y/O male. Approx. 2.5 wks ago, I noticed a small, itchy lump on my left jawbone. It appeared much like a fresh mosquito sting and had a mild itch. Four days later, its size had grown considerably and the itch was more pronounced. A couple days later the size of the thing had become very noticeable and there was pain--no more itch, but there was tolerable pain (on a 1-10 scale about 3). There was also bleeding from wounds on top of the painful hard bulge that I do not know what the cause was. I went to an urgent care and was seen by an MD. He prescribed Doxycycline Hyclate 100MG caps twice a day for 7 days. On the last day of the medicine, I visited a dermatology practice because I had not observed an appreciable improvement in my condition. I was seen by a FNP and she prescribed Hydrocortisone Valerate 0.2% cream. I have seen some minor improvement--the skin lesions seem to be healing and the hard kernel under the lesions has shrunk some. Also, I cannot feel that lump when I put a finger in my mouth and fry to feel it from the inside. Any suggestions you can give me pertaining to whom I should see or what I should do will be appreciated. (S) Chuck Ballard