What Causes Small Bump On Penis Tip?

I just noticed a tiny bump near the opening of the tip of my penis and I was recently tested negative or non-reactive to any STD/HIV. I am concerned about this "bump". There is no discharge, but it looks like a papule. I have RX's for Hydrocortisone ointment 2.5% (for facial dryness) and Imiquimod Cream 5%, for a tiny raised spot on the upper side of my penis.

Can I use either of the above to treat the bump and is a Urologist the correct doctor I should make an appointment to visit?