Am I too late to claim for 2015 accident?

I had quite a bad accident in May 2015 caused by a big spill of diesel on a roundabout. I was in and out of hospital for many months and have still not fully recovered. I suffered physical injuries and have been very emotionally affected. I recently found out that I could have claimed compensation for my accident but when I tried to do so I was told that I have missed the deadline for claiming. Is there any way around the deadline? Any assistance you could offer would be gratefully received as I do feel I deserve some sort of compensation? Stuart Ritchie, email