You generally have just two years to file a lawsuit for medical malpractice, but there are exceptions. It's hard to say without more information. I'd be happy to talk to you about your situation and the possibility of a lawsuit. I know some good medical malpractice attorneys in Chicago if you need one. Feel free to contact me. 1-800-517-1614.
It's quite late too long before you decide to file a lawsuit. Perhaps around six months after would have been better.... but i'm not saying that it really too late. It's still worth a try and you'll nee to consult an attorney regarding your concern and discuss every detail as possible. There are a lot of considerations in filing a lawsuit and one big factor for that is time.