I would take him to see the vet and have it looked at and see what your vet recommends....and if it doesnt go away in a few weeks, then definitely have him/her biospy or aspirate it. My dogs have had lots of lumps and bumps biopsied. Once I took Java in for a pimple. The vet popped his zit and we went on our merry way. Then 2 1/2 yrs ago what I thought was nothing turned out to be his mast cell cancer. (He had surgery and radiation treatments and is fine today.)
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