Retracting my foreskin hurts

I'm 21 and uncircumcised. While growing up never had the idea that the foreskin can be retracted and has to be pulled back until probably a year ago. After getting to know this , I tried pulling the skin back, and do so daily. When not erect, I can pull the foreskin back pretty easily, so its okay in the shower in terms of hygiene. But when erect, i really have to struggle, and when I do manage to pull it back, it sort of gets stuck between the head and the rest of the penis, and hurts a lot, any suggestions if I should continue to pull back or what?

Also, because I had never touched the head of my penis before, (not even now when I masturbate as the foreskin covers it) Any suggestions on how to lower that sensation, I'e tried masturbating by just stroking the head, and came too fast, and normally I last much longer.

Also, will this affect my sex life in any way(I'm a virgin)