Look at the whole day
A journey, appointment and social plan can add up. Before adding something else, notice what the day already asks of you. There is no universal energy budget.
Make one thing easier
Consider simplifying a meal, moving an optional task or leaving time alone after a busy activity. Rest might mean quiet, a familiar interest or another activity you find comfortable.
Change the plan without a score
A plan is allowed to change. If you repeatedly cannot manage essential daily activities, seek support from someone qualified to help; a schedule cannot explain the cause.