With first morning urine, make sure you've heald it in for at least 4 hours, this makes the urine more concentrated. try drink little before going to bed to prevent more trips to the toilet x
Cycles can be quite shifted and some times periods can be lighter, heavier, shorter, longer, etc. If the last itme you had unprotected sex was two months ago, then you should be testing postive. You could get a blood test to try to confirm. If you want to do another at home test, wait a week and test with first morning urine but if you were pregnant, you should be showing up on a home test by now.
well, it is possible that you could be pregnant, but pregnancy tests are pretty accurate if you used it correctly.
did you drink a lot of fluids before testing? If yes, you could have diluted your urine, resulting in a false negative.
did you read the test in the time frame given?
it is best to use first morning urine, however, if you are 2 months along in pregnancy, first morning urine should not be necessary.
There are a lot of thing that can delay a peroid. Your age for instance. Lots of young women experience irregular cycles. Stress, weight, birth control and tons of other factors can contribute to this also.
try not to stress too much. take another test in a day or 2 using your first morning urine. Good luck & next time protect yourself!