From what you have told me, it does appear that Quincy has a mild digestive disturbance. If this is minor and due to something Quincy ate or stress, the best thing to do for now is to fast Quincy for 24 hrs. This will allow his tract to calm down and heal. After the fast, feed a meal of boiled chicken ¼ and rice ¾. If this has helped, wean Quincy onto the regular meal over 2 day’s period. At the same time, you can give Imodium AD 2 mg caplets at 1 caplet per 30 pounds of Quincy’s weight given every 8 hrs.
It is extremely important to have your dog seen immediately by a vet if your dog continues to have severe diarrhea. Even the dehydration from this can cause your dog severe complications.
If this is not successful, you will have to have your vet examine Quincy to determine if there is something else such as a protozoa or infection that is causing this diarrhea.