Canny employer didn't give me my signed contract

I have great problem because I worked in the restaurant. Everyhting seemed to be claear and I signed the documents with my employer.  Anyway, I was not given the contract. It was not given to any of my foreign friend from job.

I fallen down from the stairs in the kittchen. I simply tripped and I hurt my left leg. I felt pain all night long and when I woke up  on the next morining, whenmy employer come over with his friend. The mentioned freind took me to the doctor and then to the hospital.

I had serious fracture and the operation was neccesary. I spent a lot of time in the hospitals and now i still have to see my physiotherapist regurally.

As long as the place of the accident  is concerned, there are incorrect information in the medical documents. Furthermore, I was sober when the accident occured. I have witnesses who will confirm it.

How to prove that the employer disregread not onlyme but also my collegues who still don't have handed contracts? Noone feels safe after my accident. Where should we report this situation?