Can the expression "fully booked" be used metaphorically legitimately?

I'm an illustrator. Can I say "I'm fully booked" to mean that my schedule is full?

I've always heard the booked verb applied to "performative" professions: Models, event planners, singers, etc. Never for pure service and creation-oriented occupations as on-site technical support providers or painters. You book a model. You don't book a writer.

If this expression isn't appropriate, how else could I word that "schedule" sentence without being so passive or mouthful?

"I'm fully booked." or "I'm booked up." is common usage. A quick look around online suggests that it's common in British English than American but I don't think any of us "Yanks" would be confused or even momentarily surprised to hear it.

Originally, theaters and restaurants were booked and people were just busy but I think we can all be booked up now.