Help me... I’m so Confused

Ashley

Af is due on Sunday. I took a test today because it said 3 days early gives a 88 percent accurate result. Well it was negative. But now I’m getting cramping. But normally I don’t get cramping 3 days before... 1 day at most but usually a few hours before af. Also the cramping seems to be more on the right side and sometimes central but mostly right. What do you think is going on? Because I’m very regular