I'm a little confused and frustrated my period was 15 days late and I spotted for a day and then I had somewhat heavy bleeding for another, so a two day period and that was the 15th I took a pregnancy test it was positive but one of the lines disappeared and I waited until the other night and took another and the test was only supposed to take 3 minutes minutes to say pregnant or not pregnant and it took 15 and said negative for the last month I have been very neauseated and have puked, I'm exhausted, my lower back hurts, I have had cravings. Could I be pregnant, and the hormones just not be showing yet?