Hey There, I have had hashimoto's since 2016. I can so relate to your symptoms symptoms of headaches, palpitations/PVC's, chronic fatigue, occasional nightsweats with this. I do not have the nausea & dizziness. Thyroid disease can cause a lot of issues. To be honest, when the palpitations started with me, I went to a cardiologist as they would wake me up in the early morning. My heart was fine but I was diagnosed with PVCs. I don't know what thyroid med you are on, but, could that be causing the nausea & dizziness? I have the nightsweats around 4:30 in the morning and facial flushing and I believe it's thyroid related. I also have Graves Disease and take Methimazole for that, so I have both thyroid diseases and I fluctuate back and forth between Hypo & Hyper. I have never done anything halfway in my life! LOL. God Bless You. I am praying for relief for you.