I had a pimple on my penis which I first noticed a few days ago and I thought to just leave it alone and it ll go away but it got bigger so all I did was touch it and the white part (top) of it just popped off, no blood, no puss, nothing came out. Now there is just a hole on the side of my penis where the pimple was, the best way top describe how it looks is a doughnut, the middle is just a hole now... what do I do?