There could be several reasons for a missed period. The causes for it will depend on factors such as your age, lifestyle factors and whether you are sexually active or not.
You have correctly done the right thing when you missed your period which was to perform a urine pregnancy test. That would be the most important thing to rule out with a delayed period.
If the urine pregnancy test is negative and your period is still not here in a few weeks, you may consider repeating the test to ensure that the negative test was not done too early.
Other than pregnancy, a delayed period can also be caused by lifestyle factors such as stress or any changes in your recent lifestyle. However, it would be good for you to consult a doctor if your period is delayed for a prolonged period of time (eg several weeks) or if this becomes a persistent problem.
Hope this helps!
Regards,
Dr Michelle Chia