why does my car kick back when i shift to reverse

You could have bad CV joints or bad motor/transmission mounts. I bet you hear a vibrating noise while driving.

yea i do hear a sound. i was told i might have to fix the trans valve body

That too possibly jex

It could be... But usually if a valve body is about to fail, it sends a code to the computer and it can be read with a diagnostic tool and it would probably flash a light on your dashboard. Be aware that a symptoms of a failing valve body does not always include just shifting from park to drive or drive to revere... It has many more symptoms that are usually there like incorrect up or down shift timing, hesitation, harsh up shifts/down shifts, shuddering, and sporadic shifting at steady speeds. I would get your CV joints and engine/transmission mounts checked out before you do any heavy transmission work.

is it a aut or stick car?

its auto

might be tq converter also or low on trans fluid id say take it to a trans shop that will take a look for free and listen to what they have to say