20yo guy - bunches behind glans

I'm almost 20 now and I've always had a tight foreskin. Before finding this forum today I've been soaking my foreskin in warm-hot water and just holding it as far back as I comfortably can, after which I rub in some cream and repeat this once or twice a day. I've just read the post on here about stretching using two fingers inside the foreskin and I'm going to follow that from now on.
Anyway I just wanted to ask, is it common for people to have problems with paraphimosis and phimosis? I can, with about a minute of stretching, relatively easily get my foreskin past my glans when flaccid. However there's always a slight increase in blood flow and it gets stuck. I can push it back but now I'm nervous to retract it because I think that getting an erection when its stuck behind the glans could do serious damage.
When retracted I notice these small white lumps that I routinely try to remove, is this smegma or soemthing I need to worry about? Some are visible in this picture taken just after stretching where the foreskin got stuck http://imgur.com/uEov0HQ
I was also wondering if anyone knows approximately how long it will take to get from this stage to retracting when erect?
Thanks for any help. Source:http://www.network54.com/Forum/244184/thread/1427096730/last-1427138756/A+few+questions