seriously, we are just going round in circles - anything that anyone guesses is hardly going to be helpful - if i "guessed" that from the info given, you'd be found not guilty, that's hardly going to help you when you are sitting in prison, conversely if i "guessed" that you were going to prison for 18 months, how would that help?
I can't stress enough that only you know the facts of the case pertaining to you, because you can hardly give a comprehensive representation in 4000 characters per post. The posters have pointed you to the relevant documents any judge will be refering to, so you'll just have to work it out yourself how likely things will be to happen, or even better, speak to your solicitor who will have the benefit of ALL the facts plus experience in this area. You need to speak to your solicitor about your defence of "self defence" too, because i'm not sure that hitting someone first is self defence.