If you are ever feeling miserable, then I recommend playing some Scarlatti. Even better, play it on a harpsichord. It is a proven fact that you can never be glum whilst playing the harpsichord!* Even this Scarlatti sonata in a minor key is relentlessly jolly and optimistic. I just love the bouncy motif used throughout, this starts around 15 seconds into this video which is played by French pianist Alexandre Tharaud.
*This is not medically proven, but I am sure it could be!
Scarlatti doesn’t work on a clarinet 😛
(sorry!!!)