Sony Sigma 350 and Spare lens in camera bag knocked on floor and Camera fell out. Camera works fine with Tamron lens (55-200) that was attached but Sony lens (N50) doesn't. Everything is very dark seen through Sony lens and flash, for example, doesn't work in autofocus
Physical damage is always a tough one to call - if you are sure that it is broken it can sometimes be more expensive to get a repair than it is to get a new one. The best thing to do would be to take it into your local photography specialist to get it looked at and then you will be able to make an informed decision.