What point in your life did you figure out what you wanted to do for a career?

I'm 24 (f), unsure what to do with my life. Others around me seems to know what their doing. At what point in life, did you finally realized that this is what you wanted to do?

I hope that by next year, I'll finally be able to find a purpose in life or something that I like to do and can see myself doing until I grow old.