I had sex the 14th of feb and got my period the 19rd of feb. from the 28th through the 4th I was nausious everyday in the morning at the same time. My breasts feel fuller since this past Sunday and I have been eating a whole lot and craving certain foods together. I am ver tired and have had some lower back ache. I took a pregnancy test last Friday, the 4th and another on Tuesday the 8th and they were both negative. I also had some cramping on Monday the 7th. My next period though is not due until around the 19th. Could I be pregnant?

You could be pregnant, but you will have to wait to see if you miss your period for a pregnancy test to be accurate.

OK. Would I get an accurate answer on a test if I took it a few days before my period is to be due?

It's always better to test after the missed period for better accuracy.