Would I say that colouring these sheets made me happy? No. However it did take my mind off things that worried me even if for a little while. I get this same satisfaction when I set out to solve a puzzle. Focused. It is probably my stubbornness that plays a large part.
I will get the same feeling of focus cooking and baking. Today I made a vegetable soup from scratch. I had to prep all of the veggies first, then the process begins; adding, tasting, adding more, tasting more, until the soup is what I had imagined it to be. This takes a long time. Because of my illness the prepping today took me about three hours. My hands and arms were sore and painful, but I did it anyway. I get so much joy out of making soup. Joy = Happy
If there is something out there that you like to do, that takes your focus but gives you joy, just do it. Do it as often as you like. I have to stop typing now, my hands are getting tired.