Diaper rash

My son is 11 months and has been on antibiotics for an ear infection about 8 days and has had no problem up until yesterday he started getting diarrhea and it hasn't went away. Its not much but its so frequent. I have to change him every hour or less. Ive tried probiotics, baking soda baths, oatmeal baths, triple paste, and hello bello diaper cream. Hes still so sore that he screams and cries soo bad when i wipe him :( i quit giving him the antibiotic because this is getting way too bad. Hes eating and drinking fine and his stools arent very runny but idk what else to do. 😭