Brief Answer:
Dietary and over the counter suggestions:

Detailed Answer:
Hello and welcome,

I am sorry you are having so much gastrointestinal trouble. Did this come on suddenly? How long have you had it? Have you traveled outside the US? And have you been having fevers?

Pepto Bismol can be helpful if there is a gastrointestinal infection, which it sounds like might be the case given that you've been feeling cold/hot. The bismuth in it can be effective for mild infections.

Don't be alarmed if Pepto Bismol makes the stool black or grey. That is ok.

Simethicone (Gas X) can help break up gas and may help with the belching and gas.

You might want to consider a probiotic - one that has a large amount of lactobacillus acidophilus and bifidus.

Now about foods: eat small amounts (not full meals) but more frequently. This can be less taking on your intestinal tract. As we don't know what is going on without a physical exam and some tests, I'll give general recommendations for foods that are easier on the gut.

Avoid greasy foods and meals with high fat or oil content.
Avoid beans/legumes.
When eating cruciferous vegetables (broccoli, XXXXXXX etc), cook them well.
Limit garlic and onions.
Avoid spicy foods.
Cooking foods generally makes it more easy to digest.

Eating simple, whole foods right now may be most helpful. Boiled chicken, baked fish, cooked vegetables, rice.

Sometimes people develop intolerances to dairy or glutens (such as wheat, barley, rye). You can eliminate dairy for a week or two and see if it makes a difference, do the same with glutens. But not at the same time. You want to control which things you are eliminating so that you can see which ones had an effect.

I think Zantac is a good idea. It is a safe acid reducer compared with proton pump inhibitors.

I hope this information helps. Please let me know if I can provide further information.

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