Advice Needed - Toilet Trained Dog Nighttime Pooping

We recently came back from a holiday to a poorly pup - our dog is 1 year old and fully toilet trained, a complete creature of the routine usually. He has been suffering from Diarrhoea for about 7-10 days now (no sickness, excitable, playful normal behaviour, just very runny stools) the vet initially put this down to pining for us and missing us, so advised us to leave it for a few more days. Since returning the problem has continued and we are now awaiting the results from his stool samples from the vets. The issue is, is that he is currently only passing very small amounts in the day - 2/3 very small runny stools, and then at night we are woken up around 12-2am to 3/4 piles of runny (cow pat consistency) poo's. Obviously we will await the results to see if a parasite is causing this, but as the vet says its going to be another 5 days, does anyone have any experience of a similar issue?
He is fed at 7.30am and 5pm, walked at 7.30am, 2pm, 5.30pm with free roam of the garden all day as I work from home. (Any further info needed just let me know!)

 

Thanks so much Merlina - it looks like we might have the same emotional pup syndrome! He's a working cocker too, and I think because he's so used to having me around all day every day when he's thrown off by a holiday it really gets to him. We popped him on white rice and chicken at the vets recommendation but that didn't seem to do anything, so maybe we will try sweet potato and white fish. Probiotics are a great idea and I will drop the vet a call about that. Thanks so much for your help and advice.

 

Thanks so much to you all for your advice and help. We finally got our test results back from the vets and it turns out he is carrying Camplobacter. He is on a course of human antibiotics to try and rid the parasite and fingers crossed he will be on the mend very soon!