I've heard of all of these possible hypothyroid symptoms, including the feeling cold and tired. Again, if the thyroid replacement is sufficient, one should likely not have such complaints anymore. I certainly would never ever blame Synthroid for any weight gain. Low thyroid functioning? Maybe, but if well controlled, much more likely something else would be causing weight gain. Another med? Aging? Mental health issues, themselves?

I hope you get passed your non covid bug, shortly. Hopefully all of these viral things will calm as the winter head towards an end.