Where to begin...

I'm 18 and my left testicle hasn't grown since I was in elementary school. It's about the size of one of those small marbles, and is dwarfed by my right one which is the normal size. At certain angles it looks as though I only have one... I've heard that it's normal for them to be different sizes, but i've also heard that if one is far smaller than the other then it might be a sign of cancer. I haven't had any issues with this yet - no pain or anything - but it has always kinda bothered me.

Related to the stuff above, i'm not so sure about my ejaculation. It doesn't really seem like enough is coming out when I ejaculate... Less than the amount of shampoo I use on my hair, and my hair is pretty short. Also, my semen just kinda drips out. I've heard that it has potential to spray up to two feet, but mine doesn't even shoot three inches.

Finally the problem i'm most worried about... I was masturbating when I was 16 one time, and as I came I felt a little stabbing pain in my groin, up and to the left of my penis - about where the pubic hair stops growing. I realized minutes later to my utter terror that I seemed to have lost half of the control over my penis. In more detail - I can barely raise it up at all using the muscles down there like I used to, I can't force myself to piss harder like I used to, and it takes longer to get an erection, it's tough to keep it hard and it's tough to keep it up - it likes to just flop over. Also when I do ejaculate, my penis shrivels up really quick and is useless for a long time. I'm sure it would function well enough to have sex (if that ever happens), but it is still very frustrating and has always had me feeling a little down. I know that this isn't psychological, and it doesn't seem to be the usual type of ed. I know I should probably get it checked out, but that would mean fessing up to my parents about it all, and that would just be awkward to say the least.

Any help??? Thanks.