Tip of my penis head is red/swollen?

I'm 15, and a virgin... However the Tip on my penis on the head is red/swollen and the tip is not really open, but looks like a slit.. It's been this way for about 5 months and i have no clue what it is. I went to the doctor but he just gave me some cream that has done no help at all, and im positive it's not an STD or anything such as that. If anyone can help or has a similar issue please tell me im kind of scared. BTW it doesn't hurt or anything such as that.