The jury have common sense.The case is committed for trial so you can have the benefit of that common sense. Listen to your lawyer and counsel.. They are much better placed to see your case and its merits and what a jury will make of the evidence of the other lot than you are.! And they know the law.
Doing it your way is like committing suicide before you have an operation, for fear that you might not live even though your doctors think you will ! It's nonsense.
By the way if you plead guilty nobody can promise you won't go to jail anyway. (Just thought I'd cheer you up! ) Better plead 'not guilty' then ! On your account, you're not. The jury,or at least ten of them, have to be sure beyond any reasonable doubt that all the evidence, including yours, proves that you could not possibly have been acting in self- defence. The prosecution have to prove it.You don't have to prove to the jury that you were.