Is this unfair, or am I just being spoiled?

Ok, so a long time ago I got my license and I REALLY want a car. When I ped my test my dad wondered why I wasn't excited and I wasn't trying to be manipulative or anything, but I broke down crying because I was thinking about how I'd never get to use it because I don't have a car and we only have two cars-one for my mom and one for my dad. And he was said well, you can drive to run errends. And I said I want to drive to school! Theres no point in a license if you don't get to use it. He said I could use the mini van (ew its a plymouth too, white. Huge. Old. Embarrasing, but I drove it anyway, thinking whatever, it won't be like this forever.) on the days that he was home or didn't have to work (my dad is a cop and my mom is a homemaker). And that eventually I could get a car, it wouldn't be immediate, but I would get one. I was esstactic and I promised to get good grades and get a job to pay for gas and insurance. He even looked up some on the internet because a family friend found one online cheap. He even asked one of his friends if he knew any cars on sale (I asked for a cheap one too, since cars are soo expensive). I was so excited. And now my dad went back on his word and said I could never get a car. (And no I didn't do anything bad, on the contrairy, I've been really good, grades better than ever-4.0 and I'm looking for jobs. ) Its not fair. If I have kids, that's going to be my biggest rule- Never make a promise you can't keep or make a promise before you think it through. I don't care how small the promise is, because disappointment is the worse feeling in the world and the cruelist thing to do is make somebody hope and then crush them.