I just recently started having sex with someone, as far as I know she said she has been tested and is clean. Each time we have sex we use a condom. A couple days ago, I notice a pimple like bump on the glans on my penis, it doesn't itch or burn. It's recently reduced in size, but I have no idea what this could be. I have had no other health problems, no itching or burning anywhere, no fever, no swelling anywhere. Should I be worried about anything?