She asked me what I was doing today (I believe as a way of letting me know that she was going to the lake without me but I'm not sure) and I let her know that I had some work to tend to.
You closed off her invitation by telling her you had work to do. Maybe next time, just tell her you haven't decided what your plans will be.
It is not about what you feel should work in your M. It is about doing the work that gets the right results. Do what works!
