The clownfish probably won't protect the anemone from the shrimp. Normally cleaner shrimp cause a lot of problems in anemone tanks. They irritate the anemone. They will steal food directly from the anemone's tentacles. Even if you keep the shrimp away from the anemone while it is eating, I have had shrimp actually go into the anemone's mouth and steal the food out of its stomach.
If you want to keep your anemone happy, get rid of the shrimp.