Hi. Im 32 Yrs With Regular Periods Around 24-28 Days

Hi. Im 32 yrs with regular periods around 24-28 days cycle. i got my periods on 17 march 2015. I was on Ovofar from day 2-6 and duphaston from days 16-26. Made sex on 20, 23, 26th day of cycle. Its been 37 days, i dint get periods yet and when i did home urine test on 33rd day it was negative. what could be the reason. what shud i do now. will there b pregnancy possibilities. when shud i go to doctor. Please suggest. Iam also taking folygel DHA caps from past two months. All medicines are prescribed by Gynecologist.