What Causes Hyper Sensitivity On Glans Penis?

My penis head is sensitive. I can pull my foreskin back easily. But when I touch the head or something falls upon it (may be any cloth or underwear or anything) it hurts badly. I am also not able to do drug coating of any cream on it as it hurts badly. I have no problem pulling my foreskin back. Is it normal or what? I am not able to do sex.