I too want to welcome you to Healing Well. I know it is very disheartening to go thru this no one not knowing or the ones that are not willing to take an extra step to find out why something is going on with a person. It can just about drive a person nuts. At least when given a dx we usually end up knowing which direction to take.
I see you have just started Cymbalta. Cymbalta is a drug that has to be titrated up slowly. I was put on it for neuropathy in my feet and hands and it took a bit to get me on the right dosage before I could tell it was working. I am thinking my increases were done at 2 week intervals. It worked great for quite a while for me.
Has anyone ever done a doppler on your legs to check your blood flow? I have circulation problems that causes my legs to swell plus I also retain fluid. I take a diurectic for the excess fluid. I have had sores to develope from too much fluid in my legs and the fluid would weep out through the skin causing sores. I went thru something simliar to you with a foot problem that went on for 3 yrs before anyone could tell me what caused it. Of all people it was my rheumatologist that knew exactly what it was. As it turned out its indirectly related to my crohns disease. I get blisters that go inward to the tissue, they are never raised like a regular blister on the skin. I have to keep a close watch because infection is always lurking with this stuff. Sometimes the pain and pressure gets so bad, I will take a clean needle dipped in alcohol and drain them, I have had them drain for as long as 24 hrs. Eventually the skin starts drying out and several layers of skin peels off causing sores to develop When they get to this point is when the pain really gets bad because many times its nothing but raw skin. It takes these forever to heal. I had one get infected about 2 months ago on the side of my foot, it still has not healed, its still in the peeling process.
Someone else mentioned a dermatologist and this may be a thought to entertain. They certainly know skin conditions and they can take a biopsy of the skin involved and find out if is an infection, or even a fungus. I had 3 different drs look at my feet and they did not have a clue lol. one told me it was a fungus and a really bad one and to go home and throw out every pair of shoes that I wore all the time. He claimed the fungus could live in the shoe fabric even with me bleaching them. Well, thank goodness I did not do that. It was not a fungal infection at all lol.
I do not think I have been much help and I wish I could offer up more. Just do not give up, keep at it until a dr can tell you exactly what this problem is and why you have it.