Erectile dysfunction

Hi, I am 27 yrs old boy. I`m actually having an erection problem which I think is very serious. First of all am not totally erect when i masturbate and the frequency becoming erect has drastically decreased.  3 months ago i used to be fully erect and i used to masturbate everyday but now I can`t feel that erection coming.  I get partially erect and thats the most frustrating part.  I remember that the lower part of my penis(testicle area) had a collision with the saddle of my bicycle last year while i was riding. It was painful only for a moment and after a few days there was no pain.  The second thing is that when I stand for more than  one hour I feel a pain at my left testicle.  I dont really know what to do in this embarassing situation.  Can you please give me some advise????
I need help!!!

[SixStringer]

Something of this nature should be run by your physician.  It is nothing to be embarrassed about, as they deal with things such as this all the time.  When you make the appointment, just say you want to see the doc for a couple of male issues.