Why do I itch with white discharge?

Pregnancy might be a possible. But you must visit a gyneclogist to confirm it, they can suggest you necessary tests to confirm pregnancy

By assuming a standard ovulation cycle of 28 days, ovulation occurs at the time of the next period which is 14 days prior to the period. Thus, your last period began on August 20th, hence you are likely to ovulate on or around September 3rd. Some indications of ovulation are differences in the thickness of cervical mucus, slight abdominal pain, and a rise in basal body temperature. You can also use ovulation predictor kits to check for ovulation.

there are SEVERAL reasons for delayed menstruation in teenage girls. Puberty timing varies widely. Hormonal imbalances can delay menstruation. Excessive exercise or underweight can impact menstrual cycles. Stress or medication can also delay periods Consult with a DOCTOR.. 

The indications of instability, as well as frequent urination, are the side effects that come with the intake of a levonorgestrel pill, in some cases. One of the repercussions of this pill is an alteration in your menstrual cycle, i.e., a late period. More often than not, it is a typical reaction to developed bleeding, i.e., the moment after the pill is consumed when the period is expected. Keep a cool head and try to avoid getting stressed out, because stress has an impact on your period. If you did not have your period after the first week or two, it is advisable to take a pregnancy test to be 100% sure.