I am day 12 post iui and i felt a little nausea this morning for about 30 minutes my boobs are still a little sore but not as much as they were, well they tend to change from day to day in tenderness, lastnight i felt twinges on my leftside only and i had a headache, i am drinking 2 plus litres of water a day so it must be from hormones....my period is due around the 8th march, i feel like i am showing positive signs but when i test it comes back negative, is it too early to show or could implantation still be taking place? My blood test is on the 6th