I'm slowly. (Never have sex. I know I'm not preggers.)
Answers: It all depends.. Stress can mess with your term. OR ...How long have you have your extent.. I know for the 1st 3 years I had mine, I was never "regular"... I would progress 40 - 50 days between periods.. and I wasnt sexually active at the time any.. So it just be a hormone thing.. Even immediately many years later, if I am not on birth control, my period are still not normall. I would suggest talking to your mom, or see a doctor. Good Luck.. I am sure things are ok. As far as the vitamin.. I am not sure.. .
How old are you, when did you gain your first period?
Have you been messing around?
People who own started their periods not too long ago can have nonstandard periods for the rest of their teenage life span.
If you have been messing around, you might hold gotten semen on your opening, and you can get pregnant too.
Sometimes vitamins can affect your hormonal stability.
Are you stressed? Stress can also be a factor.
If your time doesn't come soon, call up your gyno, or doctor. I'm sure they can figure out whats going on..
it could be any number of sound problems so if your really concerned then you should go to the doctor to find out what's up.