A blood test could rarely, if ever, be a bad idea. Since you are so young and you have erections, I am inclined to believe that your problem is of psychological nature and that you don't need at this point a blood test. But it is the only way to be sure that your hormones are OK.
so a blood test to see what my hormone levels are is a good idea?
> so if its not likely for ED, what can i do to help myself out in this
> situation?
Certainly not viagra and the like. From your description ("and the harder we would try the more it would go down") the cause seems to be an anxiety condition about sex. You first need to calm down and to not think about the act of having sex. If there is no real problem with your sex drive and/or hormone levels, it will just happen one time.
um, yes to morning erections, and the spontaneous erections, no wet dreams, and yes, i have masturbated before.
and im a virgin, but i have received hj's/**'s and ejaculated. so if its not likely for ED, what can i do to help myself out in this situation?
As already said, do you have a normal "sex life" as a single? That is, how do you react to masturbation? Do you have night/morning erections or even spontaneous erections during the day? Wet dreams?