Can you estimate the size [e.g. 'dime-sized', etc.]?
Is it tender?
Does it seem to contain fluid?
Is it warm to touch?
Once you've answered these questions with clear, well-thought out answers, I will reply with my Expert Medical Opinion. Your answers will enable me to get closer to an accurate assessment, which is critical to obtaining successful treatment or cure.
Thanks, XXXXX XXXXX Your Online Family Doctor
There are 2 Main conditions this could represent:
To positively identify what your lesion is--you need to have a Physical Exam with a trained doctor, to confirm correct diagnosis, so that proper treatment can be rendered.
I strongly advise that you see a doctor tomorrow to get this properly evaluated.
Let me know iif you have a followup question,
Based on the size and description: No, it is not likely to go away [completely] on its own. You can try waiting a few more days--but after that [if still present], you should definitely seek medical treatment.