I think you mean that when you turn right, maps is showing you turning left, that sort of thing.
There are two modes with GPS - North-Up and Track-Up. North-Up always shows North at the top, South at the bottom, etc. Track-Up always shows the direction you're moving up. If you're used to one, the other looks "backwards". Look for the little compass showing in Maps - one end of the needle red, the other end white. Tap that to switch between modes. There's no reason to use either particular one, use the one you're comfortable with. (I always use North-Up, but that's me - it used to drive my wife crazy, she's a Track-Up person.)