What Causes Nausea Associated With Chills And Hot Flashes?

For the past five or six days, I ve had nausea without vomiting in the morning and at night. Sometimes, it is accompanied by: -chills -hot flashes -an inability to focus (lethargy) -an inability to burp, although feeling like I must -mild to moderate pain or cramping in the upper abdomen between the belly button and sternum Some other notes: -pain sometimes worsens after eating oats or orzo/noodles, so it could be gluten-related -a few days this past week I ve been fine in the morning, but as soon as I get in the car or walk into my destination, my stomach starts to act up full-force (with hot flashes and nausea); however, when I get home, all my symptoms disappear almost entirely -I do not have any history of anxiety -My last period ended around January, 1, and I m expecting my next one in a few days -I am a seventeen-year-old female.