I went through this with Georgie a couple of nights, so I totally know how you feel. He would have diarrhea all night and then run around and play like nothing was wrong. I am sorry that Luigi isn't feeling well but if it makes you feel better Georgie went to the vet got some Albon and was good to go. The vet said something he got ahold of upset his stomach. If you do feed him give him boiled chicken and white rice. I hope he feels better soon