What does this dream mean?

I keep having a recurring dream where I'm at a theme park, and the rollarcoaster derails. sometimes im on it, sometimes not. if im on it, I never get to the point where i actually die, but its always awful and i always wake up feeling unnerved. Sometimes I can go ages without having this dream, then reappears again. The reason I ask is because i had it again last night. but it was worse than ever. I was on a uni trip and got in the rollarcoaster but noticed the harnesses werent stable, so I got off again saying i had a bad feeling about it. then everyone on that carriage did the same. I could see the loop of the coaster in the distance and when the carriages started going round it they started derailing. people were screaming, it was horrible. loads of people begging to be rescued. the dream itself seemed to go on forever and when i woke up, I felt awful. I'm not weird! what exactly does it all mean? Incidently, I just started my 2nd uni year yesterday, but Im not worried about it at all, just excited. is there a connection?