I am a 51 year old female in good health. Last weekend I came down with chills that lasted two days. since then, I've had diarrhea every day. The diarrhea comes out with undigested food and a forceful gush of yellow, foamy water. Today for the first time it was semi-solid stool, but it was pale yellow. Also, my stomach is queazy and my burps feel "acidic." Also, I have some gas and perhaps bloating. would you say it could be giardia? Other than the symptoms I've described, I feel fine.