With a normal period and a negative HPT, it is unlikely to be pregnancy
. Though, you can repeat the test after a couple of days, you should go for the serum beta-hCG
estimation as it is very sensitive and specific. Your symptoms can be perimenstrual as well. Please get a trans-vaginal sonogram as well. Please contact a specialist for further appraisal of the situation and further help. Hope your query has been clarified. Wish you good health.