Thanks for the query.
Yes, you didn't have intercourse around the time of ovulation. Because according to your 30 days cycle the ovulation might have occurred on around 16th day of your cycle.
Delay in periods can occur due to many causes and hormonal
imbalance is one of them.
You better go for blood test
which will rule out the possibility.
If the test comes negative wait for few more days. If you do not get periods even after 4 to 5 days, consult gynecologist and take tablets for withdrawal bleeding.