How can an 18 year old virgin not get fully hard?

I used to get raging hard-ons that would aim straight into the air and wouldn't go down. I'm not sure when this started to change, but I would have to guess about 2 years ago. When I get aroused, I start to feel the blood pumping but its like it gets to a plateau where it wont get any harder then i can feel it starting to go away almost immidately after this.

I've been doing all kinds of research, desperately trying to find something other than a pill or a pump to fix my problem. There are a few things you should know about me:

I smoke cigarettes (I smoke about a half a pack a day now and I am working on quitting)
I smoke marijuana
I think i have phimosis (uncircumsized, obviously)
I am a virgin

I have started to cut back on smoking (by half a pack). I haven't seen any benefits so far.
Smoking marijuana actually helps, but I still cannot get a full erection
I have started stretching the foreskin and putting hydrocortisone (sp?) on it

Could my problem be related to the phimosis? When I managed to get my foreskin over the head of the penis and try to get an erection, it felt like the blood pressure was building up more than usual but i had to pull it back over, because of my extremely short frenulum breve. Also, I have always masterbated a lot, sometimes a few times a day. Could there be a chemical imbalance due to consistent masterbation (masturbation) through the years?

This is VERY frustrating, especially because of being a virgin who cannot lose his virginity. PLEASE, if anybody can help, let me know. I know seeing a doctor is the best solution but I'm afraid he will send me out empty handed, or at the very best with Viagra.

Thanks in advance.

-VCardStillInTact

[dona74]

Im not a doctor, I cant help you much but there is more than a pill and  a pump. There is shots that you take that I believe is a one time thing. Now the good news there is a high percentage of young people that this (mental disorder) so to speak that causes the erectile dysfunction.