end on a sour note

To conclude (something) with some particularly unfortunate, unpleasant, or disagreeable piece of news, information, or conversation. The firing of our head coach really ended our football season on a sour note. The CEO's speech at the Annual General Meeting ended on quite a sour note when he announced that there would be company-wide pay cuts and layoffs. Despite my hard work all year, I wasn't nominated for any awards, so my academic career ended on a fairly sour note.