It could be a lot of different things. Maybe you are constipated or you have endometriosis; contact your physician you shouldn't feel pain and you need to find out so you can return to a fun sex life.
Painful erections can be caused by a condition called Peyronie's disease, which involves the development of fibrous scar tissue in the penis. Other possible causes include priapism (prolonged erections), penile fractures, infections, or certain medications. It is important to consult a healthcare provider for proper diagnosis and treatment.
Hemeroids.The can be painful.
Bladder infection.
You are bleeding internally, in your bladder.
Among men it could be an enlarged prostate gland. Well, what if it's in a 19 year old male and after going to the hospital and being checked out, he was told nothing was internally wrong? If could be rooted in an anxiety or stress disorder. It is not an uncommon occurrence among people who had difficult childhoods.
You need to go see a doctor. This could be an STD.
You probely broke it
If your period came on and a string came out this is not good. You could have something very wrong.
Could be one of several things. Pregnancy is one of them.
Tapeworm
There really anything WRONG with it and I can't imagine that it could effect your period, BUT WHY WOULD YOU WANT TO EAT BABY POWDER?
yes, there could be more issues wrong then what was found before.