I understand how worry you are about this event. Certainly finding undigested food should not alarm you since it might be common to find from time to time undigested food especially vegetables which are composed of fiber and sometimes are not digested by the enzymes in your stomach.
However since you have also Diarrhea, this might have probably caused your bowel movements to increase and cause indigestion. I would suggest you to rehydrate yourself and try eating easy digest foods. In my opinion you might probably have some type of food infection most probable due to virus or bacteria, most probably it would end by itself.
Nevertheless watch for signs of fever and diarrhea with mucous or bloods, if you notice any of these signs or symptoms seek medical attention. I wish you a prompt recovery.
These Q&A’s are for educational purposes and should not be relied upon as a substitute for medical advice you may receive from your physician. If you have a medical emergency, please call 911. These answers do not constitute or initiate a patient/doctor relationship.