Dreams can't not work

We got given a serum on the 31st of December the year we were born to tell our bodies that in 17 years we would have a dream. And that dream would show ourselves what our career would be for the rest of our lives. People try to practice what they want as a job because you have a higher chance of getting a job you're good at. People also forget their dreams and a few try to lie to get the job they want so the give us these weird head set things that tape our dreams. The machine spits out a disc which we have to give to our teacher. But my dream, my dream didn't show me what everyone else's showed them, my dream showed me a place. I wasn't really doing anything just wandering around. Why didn't my dream work? Dreams can't not work can they?