When to test for pregnancy?

Hello Ladies,

I have a regular 28 day cycle. I have never missed even a single day delay these many years. This is the first time, I have missed my period for the fourth day while trying to conceive. I did a Home pregnancy test using pregnancy test strip. I did my first test on the second day in the late evening and got the result negative. Then took the next test in early morning sample and got it negative again. The other symptoms I have for the past one week is unusual tiredness, feeling sleepy, food cravings, bulged areolas and sensitive breasts. Just now felt nausea once. Am I showing any signs of pregnancy? Should I see a doctor now or wait for few more days.

Please guide me ladies!!

When to test for pregnancy?