What’s going on?

I am officially a week late for my period. I had incredible amounts of stress last week with my parents coming, my roommates not helping clean up my condo, graduation, and my parents were going to meet my boyfriend AND his parents at dinner at my place that weekend. Then, this week I had nausea, stomach cramps (alternating sides), and diarrhea all day for four days. And I’ve been experiencing intense side pains on and off for the last month or so. I have taken 3 pregnancy tests - Clearblue, non digital - all negative. I haven’t been to the doctor yet because it’s early and I have an appointment in two weeks. Any ideas?