Having Problem In Pulling Skin Of Penis. Had A Operation When I Was Too Young. Is It A Disorder?

Hello Sir,i have a problem in pulling the skin of my penis and exposing the glands, im 20 yrs old and just came to know that it should go back fully during erection as in movies, i have searched about it in wikipedia and came to know that it is a disorder named phimosis , actually when i pull my skin back, it appears to be attached to central part, so when pull it back repeatedly, the part of skin which is away from attachment came down till head after repeated pull but the half which is attached is stretched a little but didnt came down till head. also when i was young i was taken to doctor for a operation or something but they didnt operate it. i dont know why i was there as iwas too young but my parents used to talk that it was not open , now i think this was the problem they were talking about. sir, im too afraid , please help me