Hi,

My dead grandma has passed away about 2 years ago, and 3 weeks ago, I experienced a car crash. And at night while I was sleeping, I dreamed about me in white clothing, and my grandma in white clothing too. I think I was in heaven with my grandma. She was just staring at me, and she seemed to be checking if I was alright. The next day I woke up, did the original things that I do everyday. (You know, school and all that.) I kept thinking about my grandma. (Okay, lets just say that school's done and it was night time. Getting ready to go to bed.) I brushed my teeth, blah blah. And I was just about ready to sleep. Until the light flickered. I had just replaced the bulb before my dream. I said,"Grandma?" And the light flickered again.

I don't know if i'm mental, and I don't even know if its real. Its been creeping me out ever since!

If you were in a car crash and your grandma came to you in a dream dressed like her she no doubt was telling you to slow down or you will join her in the Spirit World.
There is nothing to be afraid of here grandparents and others quite often do visit us in dreams and you should tell her you are happy to communicate with her and you will be more careful in the future so she doesn't worry about you so much.

WELL IF SHE IS HAUNTING YOU TELL HER "GRANNY STOP HAUNTING ME"

I agree with Rosemary. There's nothing to be scared about, take comfort from the fact she visited you.

Coincidence, grief and thinking of the unknown is a bad mix.