Erectile Dysfunction?

I am only in highschool. And I have this problem.Okay so about 2 weeks ago, I woke up with a morning erection. I rolled over onto it and accidently applied too much pressure on it. The pressure caused my penis to "pop" or something like it. I didnt think much of it. I assumed the sound was from somethign else. But now ever since I couldnt get an erection. I assumed I had accidently popped a blood vien that allows my penis to get its erection but I dont know. Normally when I watch porn or masturbate I am able to create a erection pretty quickly. However now I cant even get one. And it only begins to erect when I am about to ejaculate. Can this be temporary? Because I am still able to erect, only right before ejaculation. So this indicates blood flow in the penis? Right? Ive never had this problem before. Could it be my diet? Stress? Which I highly doubt. Please I am very worried about this. I would highly appreciate your reply.