I am a 25 year old male in decent health. I recently noticed a well-circumscribed bump on my right buttocks. It is about 6-8mm in diameter and is painless upon palpation. It appears to be deep within the skin, but it does feel slightly raised. I had strep throat a month ago and received a Bicillin shot in this same buttocks, but the bump seems a good deal inferior to the Bicillin injection shot. My immediate fear is Liposarcoma. Is there anything else that this could be? I obviously plan on seeing a dermatologist as soon as possible, however, I am currently scared to death. Is there anything I should be doing in the meantime as I wait to see a specialist? Any info would be very much appreciated! I have added a photo of the bump.
Side note: I have a family history of lymphoma as both my brother and sister were diagnosed with Lymphoma HLH as a result of Epstein Barr infection.