Injured at state park?

My family and I rented a pontoon boat for the day at our local marina which is part of a state park. At the end of the day apon off the boat as soon as my feet hit the wood dock I slipped and fell. My knee hurt pretty badly at first it popped and started buring.. the guys that were working there (they looked like teenagers) asked if I was ok but didnt really show any compion. We went home and now 2 days later its starting to hurt more and more.. I really think I did some damage now. The thing is we dont have insurance yet. My husband just got a new job and isnt eligible for insurance until november. what am I supposed to do now.???