Hello,
A curved penis can be present at birth or result from a traumatic injury. In most cases, a curved penis does not affect erection, sexual performance and urination. There is no problem with your penis. 15-20 degree bent is absolutely normal for a penis.Nothing has to be done.You will not have any problem during intercourse. Every penis is bit bent and a slight bend is normal.
But if however if your penis is bent to the left or right so much as to make it difficult or even painful to enter your partner during sex then peyronie disease has to be ruled out.
It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.
The best doctor to consult with about this is a urologist it may be best to have it checked out again. Do not do stretching exercises as usually it's just a gimmick and unfortunately can cause damage to the penis.