Can you get sick from eating too much yeast such as english muffins or bread products? Say you eat 2 english muffins a day or a lot of bread?

No harm at all. There's no such thing as being overexposed to yeast. Cooking and culinary yeasts (baking, beer and wine making, etc) do not infect humans; no harm no matter how much. Regarding candida and other human yeasts, are you concerned about overgrowth or "systemic candidiasis"? These are urban myths. Candida is normal (skin, intestines, genital tract). Sometimes local symptoms, but mostly harmless.