“Let me get back to you” is a whole sentence. Instant yeses are how weekends disappear.

An immediate answer gets given to whoever is in front of you, before your actual week has been consulted. The yes feels small at the time because the cost lands weeks later, in a future that does not feel real yet. A delay is what lets the decision be made by the person who has to live with it.

Use a holding sentence this week on the first thing you are asked. Check the calendar, check how you will feel on the day, then answer. Nobody minds a short wait, and the answers you give afterwards are ones you can keep.