A similar tension shows up for a lot of people on Sunday evenings. We usually blame it on dreading Monday, but research points to something else, unfinished tasks and undecided things left over from the week before.
Your mind keeps holding onto that list even when you're not consciously thinking about it, and as the evening quiets down, the list gets louder.
One small thing helps, spending five minutes on Sunday evening writing down whatever's on your mind about the coming week. Once it's out of your head and onto paper, your mind stops carrying it, and the unease usually eases with it.