all that you feel are the same as PMS
I take it since you've taken so many tests that your period is late?
if so by how many days? It could be a number of things, even simply just that your period is late..which can happen for no reason sometimes. Have you recently came off birth control or something? I know from past experience when I came off the pill...I had a normal period then the month after it was 17 days late and I was having all extremely sore breasts, nausea and cramps and was convinced I was pregnant. Things like stress and change in diet can also make your period late and you could just be experiencing symptoms of pms. I would recommend going to see a doctor :)