I have a lump on my neck. About 2 inches behind my ear, toward the back of my head, by the base of my skull. It is about the size of a dime, and feels hard. It has been there since Wednesday, after I worked out. I have tried icing, and heating, and some light massage, but it hasn't gone down or changed at all. It is painful to push on.
My question is, does this sound like it could be a muscle related to working out, or something I should go to the doctor about? I have mixed feelings about what I should do. What would you do? Thanks for any advice/opinions.
Edited: Thank you all for the advice. I made an appointment for this afternoon. Fingers crossed that it's just a muscle thing.