so this month my period is a few days late and its usually predictable and it's brown too is there something wrong with me? And I'm only 16 =(

Probably nothing wrong at all. Is there any chance of pregnancy? If not, it is likely just the fact of being a teen. Periods can be regular for awhile, then become irregular for awhile during the teen years.

Keep in mind as well that your period won't likely start on the same day each month due to the change in the number of days in some months. Being a few days early or late now and then is not usually a concern. Periods can also sometimes start with brownish discharge or end with brownish discharge and it doesn't have to be that way each time.