How you evaluate yourself is very important.  It’s really a time of reflection on your health and what you may think is healthy versus the objective numbers that are used to define healthy.  Now keep in mind every body type and build is different.  What is obese for one person is not necessarily obese for another.  Truthfully, your medical physician will be able to tell you what BMI numbers you need to shoot for.  However, if you don’t have a regular physician here are some things you can do to evaluate yourself:

Before calculating your BMI weigh yourself in the morning before you eat or drink anything. What was your BMI?  Did you feel like you were dying during your brisk walk? Did your brisk walk take longer than 4 minutes?  How much of what you consume on a regular basis is high in sugar?  How much water are you drinking?  How much sleep are you actually getting?  These are the basic questions you should be able to answer after your self evaluation.