If you're between the ages of 4 and 28, you probably grew up with a healthy dose of Disney propaganda. Our beloved princes and princesses, brave heroes and cuddly animal friends, steadfastly preach one of our dearest false gospels: "Follow your heart; believe in yourself."
Even my high school guidance counselor, when I was trying to figure out where to go to college and what to do with my life, told me in all sincerity, "Just follow your heart." She had faith that if I had faith in me that all my hopes and dreams would come true. And who knows, maybe they would have. But "what does it profit a man to gain the whole world, and forfeit his soul?" (Mark 8:36)
Serve the LORD your God and seek the help of the Holy Spirit in aligning your heart's desires with His perfect will. And yes, that means your desires will have to change. But God can change them. Isn't that wonderful?