Why im not having periods at the expected time?

Any change in your nutrition, habits or environment can disrupt periods.
High stress can cause a lot of such problems...

I would be interested to know what your society is?

You shouldn't have to visit a gynaecologist - an ordinary general practitioner would be able to examine your general health and advise you about your symptoms, if necessary - your delayed menses can be just one of those...
I am quite sure other female virgins in your society have found a fertile imagination is one way around a ban on gynaecologists, in order to have access to medical services...
A wise old man once told me "you can get away with almost anything as long as you first get your story straight"...

Hopefully your period will begin soon and then your cycle will resume as before or as soon as whatever disrupted it has settled or been resolved...

i am 22, a virgin but have problems of late period. i was diagnosed with hyper thyroidism when i was 17, i took medicines, firstly it was relief to some extent but that did not cure the problem permanently. sometimes i do get period on time but most of the time it skips i have to take certain pills. when i was 20 my doctor then did some blood tests and initially found some symptoms of PCOD (poly cystronic ovarian disease). Though it has got cured now but the problem still persists. My doctor says i am overweight and that is why this is happening but i have many friends fatter than me yet they dont have this problem. Cananyone plz tell me the solution.