1. Did you have unprotected sex?
2. Did pregnancy test yet?
3. If NO for #1, then it either hormone imbalance that doctor will usually prescribed you with birth control pill (also serve as hormone pill)
4. You might have cyst (9 out 10 women have cyst)

Hormone pill is to regulate your hormone if it went haywire. It wont affect your fertility. In fact your lifestyle is the one that affect your fertility.

You mean what is number 4? Means there is a fluid-filled sac called a cyst will develop on one of the ovaries. Many women will develop at least one cyst during their lifetime. Please make an appointment with gynae.

Usually if one month period did not come already need to check but nowadays quite common. Please go check if 2 months and your period still did not come.