3 days late!

Im 3 days late for my period. I've had cramps since Monday which is abnormal for me. I usually only get cramps the day before and the day of my period. I have had some on and off brown spotting for 2 days. I also usually get a day of spotting right before my period. I took a pregnancy test on Tuesday morning and it was negative but I've also been trying to eat better and I've been drinking tons of water so I was hoping that my hcg level was low and the water diluted it even more so the test couldn't detect it. I'm sure I will be getting my period but do you think there's any hope for me to be pregnant. Has anyone else had these symptoms and been pregnant. I've been ttc for 9 months, I'm getting frustrated!