Welcome to NeuroTalk.

Some things come to mind for me reading your post.

1) low thyroid will cause fatigue and numb feet

2) low B12 also

3) low B12 and other nutrients may occur with gluten intolerance.

4) Myasthenia gravis can cause weakness perceived as fatigue.
This is an autoimmune disorder.

There are other things that can cause weakness.. poor sugar control, pre-diabetes or frank diabetes type I or II will do it.

Other food intolerances can cause stomach upsets. Fructose is one. It is estimated that 1 in 3 people cannot digest fructose properly and it may lead to gas and diarrhea.

Lactose intolerance also may upset the stomach and intestines.

Some people with Candida infections of the bowel from overuse of antibiotics in the past can cause vague digestive upsets, gas, and diarrhea with neurological symptoms like your feet. This is due to a buildup of aldehydes from the yeast entering your blood stream.

So a visit to a good GI doctor may reveal what is going on with you.