What is wrong with my puppy?

My puppy has been at my home for about a week. all the days he's been here he has been fine. now all of a sudden yesterday he stopped eating and has started puking a lot. He stopped acting like a puppy and sleeps constantly. he stopped pooping until today he pooped a lot of blood, barely any poop. just after he pooped he layed down and started acting incoherent and wobbling his head a bit! this is REALLY scarring me, especially since this all started yesterday, he was fine halfway through the day yesterday. All I can think is it all started after I gave him some of my breakfast yesterday. I gave him a piece of my omelet a little bit of hash brown and a little crust of toast, this is the first time I gave him human food. Now he has been dewormed, had his distemper, hepatitis, leptospirosis, parvovirus, parainfluenza, coronavirus. he just got these shots on the 5th of dec. I am taking him to the vet on wednesday because they aren't open tommorow, but I am afraid he won't make it untill then unless I have some kind of advise on care until then. so please don't tell me to take him to the vet, I already said that I am so its a useless answer, wastes my time and yours, I need REAL info here. the symptoms he is having are simptoms of almost all the vaccines he has, so i really am confused, if hes had the shots, why is he getting the symptoms of them? is it possible for them to catch the virus from the vaccine?