What Is The Small Bump At The Base Of My Penis?

I have a small bump towards the bottom of my penis, i dont think its and std but i am worried, I dont want to go to the doctors for financial reasons. I got a physical and they pointed out that it could be and STD however i was never tested because i never had sex, Im almost possitive iot is a whitehead that just hasnt gone away but it has been there for a while and im getting worried, could it just be a white head?

By the way, it appears to have shrunk a little since I got it.