Missed Period

So I'm late with my period, only by a couple days. A week ago I was throwing up and high fever went to the dr and they found no signs of any sickness. Now I'm having stomach pains in my lower and upper left mainly. I can't even sleep through night because of my stomach and back pain. I haven't experienced cramping and I hadn't had breast swelling up until today. I'm not sure to worry or not, I've never been pregnant. Has anyone experienced this, pregnancy or not?

Forgot to mention I did go to the Dr for a test and nothing came up. I recently went again and I'm still waiting for a result.