Do I have an impotence (Erectile Dysfunction)?

I'm a 17 year old male, and really worried about myself.

I like watching porns and masturbate (twice a week), and I do not have any problem to get my erection on when watching porns. And I'm not gay.

But for some reason, whenever I go to school dances, I cannot get my erection on when bumping and grinding. I mean my partner did not say anything, but I'm pretty sure she thought I was weird or gay or something. My penis is about 5.5 inches when erected, and the circumference is 5 inches.

But my partner at dance did have some big booty, so it was kinda hard for me to find the "mid-section" to rub on.

So do I have an impotence?? If not, then what is my problem?
Could it be some sort of stress or pressure that I might possibly be on?

When you worry about what is going on with you, it produces stress. At 17 years of age, you should not have any ED. I think you may have been concentrating too much on trying to get a erection while you were dancing. What makes you think that "girls' expect you to get an erection while dancing?

Its not ED.You probably just needed more stimulation than you got at the time.

You do not have impotence. What seems to be the problem is more psychological. You may be putting too much pressure on yourself in that type of situation. Don't worry when the the situation is right you'll be ready to go.

Maybe it the location. Too many people