Cramping

Hey so I'm due for my period on May 24.  I've had symptoms of pregnancy in my breasts and I'm also SO VERY TIRED. I'm never tired and I don't take naps but I've taken two two hour naps the past two days and still gone to bed at 10 or 11 pm. BUT I'm super discouraged because I have cramps like I'm going to start my period and I took an early pregnancy test(first response) and it was negative. Anyone experience something similar (i.e. Mild to moderate cramping) and still been pregnant?