Talk to Gynecologist on Periods Irregularity

Hi. I am a 25 year old unmarried female. Weight is 52 kg. I have an issue of period irregularity from past 5 6 years. My periods used to delay 5-10 days from the date. From past 6 months, my cycle was regular. Periods was on date.

But this time, there is 12 days delay. I was supposed to have periods on 20 June. I am getting worried. And still there are no signs (no pain, cramps that I had 3 4 days earlier before periods)

I am getting worried now. What should I do?