Unhappiness isn't arising from what you're doing, but wanting to do something different. If you think success and money will help you be happy, think again.
I was watching an episode of comedians in cars getting coffee with Jerry Seinfeld and Tina fey. Between them their net worth must be 1.5 billion dollars, and the whole episode they moaned and groaned about being unhappy. In the end they consoled themselves by saying, at least they are not working in a coal mine.
Learning to be happy is an internal skill, it doesn't come from external success. People who know how to be happy can be happy even when diagnosed with cancer, or declared bankrupt.
One very helpful practice is to practice gratitude - write down at least ten things everyday that you are really grateful for. It can be simple things - like - "I was not hungry today - everyday more than a billion people don't have food to eat. I'm very grateful." Or, "I don't have a toothache today, I'm very grateful"
Don't give up a steady job to chase dreams - first you need to be emotionally and mentally stable to chase dreams.