Anyone know a thing or two about dogs?

So yesterday morning we woke up to our French bull dogs kennel full of diarrhea and puke. We thought maybe it was something he ate. He was fine the rest of the day but still had the runs when we took him for a walk. Then tonight within a span of maybe 20 mins he crapped all over his kennel destroying the blanket we laid out for him. He’s almost 4 years old and never has accidents in his kennel. He hasn’t had one since he was a puppy and we just took him for a walk just over an hour ago. Doesn’t anyone have any idea what could be causing this? My husband thinks it’s because he eats grass during his walks. Since I’m on maternity leave and my husband is out of work due to covid we really can’t afford a vet at the moment unless absolutely crucial then we will definitely bring him in.