The symptoms sound like they could have been giardiasis. After trekking in Nepal and eating with locals, I managed to get giardia. (Intellectually, I knew better than to eat uncooked vegetables, but I was a guest and someone offered to share their food; I found it impossible to refuse.)
In any case, I had a single 1000mg dose of Tinadazole which cleared it right up, but I did feel like I had a block of burnt aluminum in my mouth for a few days. Restoring GI flora and fauna to the point where I could eat again involved a lot of yogurt, which fortunately is plentiful on the subcontinent.
I agree -- big ups for modern medicine! It allowed me to be somewhat stupid, and not pay the true consequences. (later, on the same trip, I picked up an amoebic dysentery due to a faulty water filter while in the deserts of India. If my traveling companion had not had a stash of "just in case" ciprofloxacin with her, I probably would have died.)