It looks like what some of us believe to be "Cutaneous Stronglyloides". The more you mess with it, the more it will scatter and move to other parts of your skin, and it's very, very persistent.
Please search on CureZone for info about "stronglyloides", as well as about "Morgellon's Disease". There are a lot of smart people here who are going through--and working to end--situations like yours.
In addition, if you have dogs or cats in your house, you may have been exposed to these parasites from them, so check on their de-worming status.