You are still entitled to claim criminal injuries for your injury, anfd if I was you I would pop down to the citizens advice bureau, or your local police station and they will explain who you will need to contact to get the forms to fill in.
With regard to your compensation, it is not definite that you will receive any monies. If your assailant was in employment with a minor offence history, you are more likely to get something but if not probably very little or nothing. There is not a willingness by the powers that be to chase individuals for compensation payments.