Foreskin problem

I have a serious issue with my fore skin. Few years back i could pull back my foreskin. I used to do masturbation from age of 15. I'm 25 now.  I don't really remember when it happened; while masturbation, the tip of my foreskin got cut a little. It got cured but at the position of the wound, the skin is white in color and is hard compared to other parts. Later while masturbation, i got wounded several times and now the tip of my foreskin is white in color around the circumference. I cannot pull back it now. The skin at the tip is not elastic. I am very tensed now as I'm going to get married in 5 months. Please suggest possible