There is no spell. When you start having your period is based primarily on genetics, if you are in your pre teens or early teens you should get your period soon, but if you're 16 or older, speak to a doctor.
In fact I know quite a few people who didn't have their first period till they were 17 or 18, it all depends on your body and when it wants to begin your periods. If you are very worried then talk to your doctor, but other than that it is just patients and waiting for it to arrive.
I don't understand being desperate about it. It will come when your body is ready. If you go to age 17 without it, I would talk to doctor. Every woman is different, and our bodies mature at different levels and different times.