Ok so is it possibly to have ptsd from a dream. I've been wondering this for a while because i had a strange dream but like all my family died in it but the whole time it smelled like pure milk chocolate which was very strange but now when i smell chocolate I start to tear up and have flashbacks to that dream.

Maybe you should find a consultant.Remind your self that it was just a dream.dreams are basically made up brain stories that the mind creates They can make you feel happy, sad, or scared. they may seem confusing or perfectly rational.Usually people forget dreams but you get flashbacks this is sign of anxiety!! It is important that you remind yourself that you are safe and that you are not reliving the trauma, no matter how bad it feels. After the flashback is over, try to understand it. Perhaps write it down or talk about it with a trusted friend or a counsellor.
Also just know you are not going crazy, There are some things you can do that can help you manage these reminders of the trauma.I am assuming you are stressed so consider doing (Deep breathing exercises, Meditation, Relaxation to music, Counseling, to help you recognize and release stress,and Sleep Enough) these practices will decrease stress and anxiety . ^-^

Mri or anything that has uv lights

Pretty bad i would assume.