I have been doing some learning about Gluten and the effects of both Hashimoto and hypothyroidism.
If I remember right - someone hear mentioned some thyroid meds may have Glucose in them.
I don't know if that is credible or not though,
Have you been evaluated for food allergies, esp. Celiac/gluten intolerance? You should do this, pronto.
Gluten can cause enteropathy in susceptible individuals, resulting in both direct puzzling symptoms (including gastric), and various autoimmune conditions. Gluten caused my Hashimoto's and mostly destroyed my thyroid. When I got off gluten, my TPO decreased to zero. However it took a while on a complicated nutritional program, to heal the enteropathy.
I would suggest seeing a specialist on this. Endoscope would be my first try. Then on to another one. Good luck. I doubt its linked. But i would talk to your doctor