From the symptoms it looks like sebaceous cyst. A sebaceous cyst is a closed sac occurring just under the skin which contains a "pasty" or "cheesy" looking substance called keratin. They may occur anywhere on body but scalp, ears, back, face, and upper arm, are common sites for sebaceous cysts. Blocked sebaceous glands, swollen hair follicles and excessive testosterone production will cause such cysts.
Generally no treatment is required but they become painful then it means they are infected, Then surgical excision by traditional wide excision, minimal excision, and punch biopsy excision may be required.
It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your dermatologist. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.
Thank you so much for the help. Luckily enough i was able to go see my doctor around the time I posted the inquiry. He said it was an infected cyst of some sort and prescribed me some antibiotics, one in pill form and another in a cream. I've finished with the pill antibiotics but it's still there although much better than it was before. If you dont mind me asking, with continued use of the cream, will it disappear completely over time? or will there always be a bump there from now on?