FREAKING OUT..

So the other night I had an in depth dream about being diagnosed with ovarian cancer. I'm 18 years old and (besides general death) cancer is my biggest fear. I have been worrying about this dream 24/7 and have only told my best friend and boyfriend about it. What is wrong with me?? The other day i was watching the vampire diaries and it was the episode where someone died from cancer (won't say the name in case someone watches the show lol) so could that have triggered it?? Please help!