This may be a long message, but I really need help.

The other day I was walking home and I stumbled upon what seemed like a duck massacre. A car had seemed to have hit 7 ducks, 5 babies and 2 adults. Curious and upset I looked at the scene to notice between two of the dead babies one was still alive. I rushed over picked him/her up and brought it home. Gave it food and water and a warm place to lay. Now this is where I need help.

The duck seems to be eating fine, drinking, and pooping. But when I found it a couple days ago it had what looks to be a large scab on her head (possibly where the baby was hit during this awful accident). That isn't the problem though, the problem seems to be that what ever I do, the poor baby cant and wont walk. To be honest when its hungry or thirsty it slides or kinda crawls towards the food. She spends most of her day sleeping or sitting around feet laying parallel to her body. When I put her in some water she doesn't seem to be able to swim but just float. Any advice please! I don't want this baby to die like its family did due to someones carelessness!

Also she seems to be breathing fine, peeping a few times a day and doing normal stuff such as that just not attempting to walk, I checked all over her little body and there seems to be no injuries but the dime size scab that is now healing over.

I found her 3 days ago.