If you feel like doing something on a whim, do it. If you feel like you need to do something for yourself, go ahead and do it.
We never know when the proverbial is going to hit the fan. But we do know when it has, and we do know that sometimes we just need to let our energy out.
Of course this should be done in a way that doesn’t harm others, but the urge to do something is all the permission you need. The fact that you’re alive is all the permission you need.