am i?

i have been having "morning sickness":sick: :sick: at any given time during the day or night for the past 3 weeks. my periods have been coming along as normal but the last one (december 1)came that friday real light, then stopped, then started again that monday and lasted until wednesday or thursday. i thought that was kind of strange. anyway, i have also been feeling lots of movement in my lower abdomen, sometimes even when i’m not paying attention. but the test said neg. is it possible that my hcg levels are too low to detect on a hpt? should i go to a dr now, in case something else is up, or try to wait til my next period which is due x-mas eve?
thanks::S