What will happen to my depth perception after an eye injury?

It depends. It depends on the severity of vision loss. If vision in the injured eye is poor then depth perception is lost and has to be "re-learned" by visual clues. If vision remains good in the injured eye or can be restored surgically, then depth perception should not be effected.
It may decrease. If one eye is injured the ability for depth percepton (stereopsis) may be decreased since it relies upon the slightly different images from both eyes to give the sensation of depth. Usually most people will recover most of their depth perception by adaptation to other visual depth cues.