What Can Be The Reason For The Pain In The Ankle, Heel And Foot?

Hello, I was identified with cellulitis during the month of May, 2014. I was given an iv and 7 days of pills. My pain was 90% cured however I continue to have pain in my ankle, heel and top of my foot of which I did not have prior to the cellultis. My foot was healing perfectly. I had ankle surgery Nov. 2013 and the areas has healed completed. I have blood clots of which I am taking med for daily and it seems I can t get have my inr levels to stay above 1.6 but one time 2.9. I was observed for the clots Jan. 2014. Today my foot doctor told me the screw placed in my foot my be causing the pain. What do you think is really going on based on what I have shared and what questions should I ask next? Thanks.