What Causes Painful Swollen Foot Post Mosquito Bite In A Diabetic Patient?

Hi, I'm a 69 year old male, I have diabetes that is not being controlled well but we are working with it, last A1c 10.9, I also have only one kidney, polymyalgia Rheumatic. November 1,2014 I was bit by a mosquito on the top of my left foot. I went to a foot doctor two days later, because of red, swelling and pain in the foot. foot doctor to go to ER which I did, the gave me keflex a couple of weeks go by and still no improvement, I can hardly walk. I then went to a different ER on 11/11/14, this doctor, this one put me on doxy-cycl mono 100mg & smzitmp ds 800-160. This s eams to be working, swelling and redness are almost gone, still have a little pain when I walk. but now my problem is different, now I have a trimmer that is getting real bad, and today when I went outside it felt as if someone was spraying me with cold water on both hands and then tonight I went out same thing but this time it seam to be on my left side of my face. I my pretty scared about this and appreciate help and assistance,