Baby poo immediately after each feed, now having bad rash. Any recommendations of creams or home remedies for diaper rash?

Use desitin (purple tube) and apply generously. Ease down to desitin (blue tube) and then Angel baby bottom balm when you see an improvement in condition. Refrain from using chemical wet wipes (ie. pigeon) as well. Dap instead of wipe the butt. Ensure your last wipe is pure water (I use cotton balls dipped in warm water). Chemical residue and wiping/abrasion can cause irritation on their gentle skin, especially with that frequent diaper changes.