Suggestions please

Long story short, my period on the first of the month only lasted half a day. And it wasn't even full-on bleeding. With no cramping symptoms. I've had a regular period for the past 5 years if not longer. I've taken about 4 pregnancy tests and they've all come back negative. How many have been pregnant and experienced this? I'm waiting one more week to see if my period comes again. I haven't been sick at all but during the time I only had a period for half a day the thought of all food made me nauseous which isn't like me . The thought of the food is what made me nauseous not the actual food itself if that makes sense at all. Let me know if anybody else has experienced this