My period was late, it should have started on the 5 March, it only started on the 15 March, a very unusually light period for me. During the time i was late i had headaches, nausea feeling, stomach cramps (almost feeling like menstrual cramps), a slight dizzy spell and bloating. I did a pregnancy test on the 13 March which was negative ( i did take it in the afternoon after drinking a glass of water) could i still be pregnant or is it just hormone changes.