If the test kit is reliable and you have done after waiting few days from expected date of period then you need not repeat. Else you can repeat once more. But there are several other reasons for not getting the periods on time. You will need further evaluation if the irregular periods occurs for more duration.
Next Steps
If you are not
pregnant, take medroxy progesterone acetate tablets(10mg) once a day for 5 days. If you get the periods it's ok, else review.