When should I test again?

I have been feeling weird lately. I have my normal PMS symptoms but with added back pain and nausea. No spotting though however I did have the white discharge. My coworkers keep saying I'm pregnant but I don't think so. I had unprotected sex 2.5 weeks ago. My period is either 13 Days or 6 days late (I have two different period trackers and they are 7 days apart). I tested last Saturday when my period was officially late on both apps. When should I test again?!