Worst Symptoms Include: -Constant Nausea Throughout The Day -Feeling Hot

Worst symptoms include:
-Constant nausea throughout the day
-Feeling hot in certain areas of body (stomach, neck, wrists) even if other parts are cold
-Stomach pain with diarrhea 3-4 times a month

Other symptoms:
-Insomnia- ability to fall asleep but wake up every night for several hours
-Gross taste in mouth with occasional heartburn
-Excess saliva
-Racing heart
-Nausea when extremely hungry

I have been diagnosed with hyperthyroid and IBS. I started low dose Tapazole just over a week ago. Many of my symptoms are in line with hyperthyroid and IBS but I am desperate to stop feeling sick every day. Could there be some other underlying issue that is contributing? Could IBS really be making me feel this sick every day? I've taken ever other stomach test under the sun and they have found nothing. I stopped eating gluten several years ago, which helped significantly but symptoms seem to be coming back more frequently.