I would save a minimum of 20% percent of your income for a rainy day fund. Aim to have 3 months worth of expenses saved up incase anything were to happen. As for retirement, it would depend on how many years you have left before you want to retire.
The question is not how much you can save; the question is how you can save your money. It is good question and I think very important too, because the expenses are increasing day by day and we will have to do something for our retirement. It is a fact that after retirement only two things work, YOU OR YOUR MONEY. If your health doesnt allow you to work then you will need money for survival.