Hi. I took a pregnancy test today (5days before missed period) and it was negative. I have been having cramps, headaches, my nipples have made a change, they are a little puffy-er than usual, but aren't sore. I have been drinking water like a camel and I crave it. I have also had some mood swings and nausea like 2 times in the past week. Could I be pregnant and just taken the test to early?