Okay so I had my last period on 24th of July 2012 it's now 18th of September and still no period so my period is at least 3 weeks late! I did a test with my school health nurse when I was 9 days late. But it came back negative. I hAve been very moody and tired and have had cramps in my abdomin. I was just wondering even though the test came back negative could I still be pregnant?

Yes and I am surprised the school nurse did not explain it.

1. it was just at the time to start taking the test, so you really need to do it, first thing in the morning, with the first urine of the day. So buy a test and do it at home when you wake up.

Urine latter in the day may have to be further alone to test correctly. You may be at that point now, if you want to try with nurse again.