Friday started diverticulitis. Been on liquid diet 3 days and taking keflex 500 mg, 4 day since sat. Have had 2 small bm today. Can I eat pudding now?

Probably. If the symptoms are improving, you don't feel bloated, you have nor pain, nausea, or vomiting, you can probably start advancing your diet back to normal. Take it slow and if your symptoms worsen, back off.