How to I cure this small itchy bump under my foot?

[louisgeorges]

It's a small, hard to the touch itchy bump under my foot and when I put anti-itch cream on it, it moves around to a new spot. It looks like when you're starting to get a pimple on your cheek. But it's under my foot.

The itching comes and goes but it's worst than a mosquito bite. I put some Lotrimin on it but it didn't do anything. When I put anti-itch cream it moves .5 to 1 inch in just hours and it leaves a small red trail behind it. Often it just goes in circles.

I went to a pharmacy clinic and she gave me Nystatin and Triamcinolone. I've been using it for 3 weeks twice a day but it doesn't work at all, the little red bump just moves around under my foot, within the same 1.5 square inch area, back and forth and in circles.  

So what do you think it is and how do I cure it? The clinic said I have to pay again for a new visit, even tough it's for the same thing, so I want to get other opinions before I go back. And if I can use home remedies that'd be even better.

Thanks for your help!