The last step is 6-7 minutes of breath watching, not 3-4 minutes. Do not modify the practice advised to you and say there are side effects. It's amazing how people miss the basics despite repeatedly made them to practice as well during the programs.
If you do wrong things, wrong things will happen to you, this applies to anyfield anywhere. suppose your Doctor advices you to rest after a surgery and this is just an example to make you understand, he advices you to take bed rest and not walk or jump around after a surgery and you do that, what would happen??
I am sure that the Teachers would have advised you not to modify it and customize it.
I have done bother AOL and Isha program basic ones and have experienced benefits from both of them.
One should nurture postive thinking and then grow on it. Like someone said, it's all about faith in anything you do.