not sure about the stitches might make make you feel a lil if she licks you knowing she gobbled the flies and flies being what they are landing where they landplus the fly guts
If she's vigorously chasing flies, probably not the best idea. The jumping and quick movements could pull on the stitches. If you can limit it for a few more days that would probably be best but cats are sometimes hard to limit. Just check the incision regularly and reach out to your vet if you notice it opening or leaking.
TRY to keep her quiet for another day or so...I've seen some kittens who just went nuts when caged to try to keep them quiet. Do your best, and watch her stitches.