I'm 15 and i ha vent have my extent contained by 4 months and i get my spell when i be 13 what could be wrong?

Well, when I first got my time. I didnt get it again until 6-8 months subsequent. Then it didnt come for another 3 or 4. then it be a little bit more regular. But, I presently get it impossible to tell apart time each month. It took nearly 3 years for it to be consistent.
You could be pregnant for one.