Tell or Say please, through what time after the first menses should ustan...

[I]

Tell or Say please, through what time after the first menses the cycle should be established or installed?
To me 14, monthly have begun two years ago. And till now they come through a different time interval. Few times there were delays for 3 months.
Whether it is dangerous?

[Pasenjuk A.M.]

The cycle is established or installed within a year if it or this has not occured or happened it is necessary to address to the doctor.