Hello, I would be happy to assist you.
Pregnancy is the most common reason for a delayed period. If you are having unprotected intercourse and are not taking birth control, pregnancy is highly likely.
The symptoms you have are related to hormones. Sometimes and abnormal surge in hormones due to stress, weight changes, exercise/diet changes, etc. can lead to a missed period. The symptoms one can experience can be similar to pregnancy.
If you did not use your first urine sample of the day after not urinating or drinking overnight, this can cause the hormone to be low in your urine. I recommend you repeat the test in 48 hours (to allow the hormone time to increase). Be sure to use a reputable brand, and not a cheap/generic brand test. Also, use your first urine sample of the day after not urinating or drinking overnight.
I wish you the best. If you have additional questions, please ask. If none, please rate my answer. Thank you.