Passenger door jammed

As a novice I took the car through water that was just to deep, got some ingress to car and have been drying out. Took the door card off to get to speaker etc on passenger side but had an emergency mid operation so put card roughly in place and gently closed the door to. Now, like a real numpty I can not open the door at all. Central locking works fine it locks and opens but I can not actually open the door and can see no way of getting to open it?

As a secondary issue and the reason I had the card off my stereo works but I have no sound and as the water ingressed an inch or so higher than speaker panels that is why \I was looking for that issue.

Help.