Lack of menstrual period, itchy and slightly burning

Hi,
Welcome to ehealthforum,
Periods can be delayed at times due to stress. Your other symptoms could be suggestive of possibility of vaginal infection (it is not necessary to have vaginal intercourse to have vaginal infection). You should consider visiting your doctor/gynecologist for examination and vaginal swab/smear test to identify causative agent and get started on treatment as appropriate. Drink plenty of water. Avoid vaginal douching, use of harsh soap or perfumes in the area (vagina has its own mechanism of cleaning itself. Use of these products harms the normal bacteria of vagina and it becomes susceptible to infection). Use loose cotton undergarments and avoid tight fitting clothes. If you are sexually active, get your partner also treated simultaneously to prevent chances of re-infection and avoid having unprotected intercourse while both of you are on treatment course.
Take care.