Maybe try Painstop if she still needs the extra relief. No point giving her something that's only making her feel worse.
Or just alternate panadol & nurofen 3 hourly, so they over lap, but there are 6 hours between doses of each.

Glad she handled the GA well. My DD didn't. She woke from surgery instantly & screaming. She remembers everything right up til she went under. Even now, 5 years later.