I'm smart in some areas , sometimes in common sense & i feel slow a lot & comprehend things slow and hesitate alot, is something wrong with my brain?

Not necessarily: First off, different people may learn better using particular methods of learning. For instance verbal, visual, written or hands on learning. Second, we all having varying aptitudes. For instance, I don't have a particular aptitude for engineering. So, I might struggle with the concepts. However, I do have an aptitude for human behavior - so learning in that area comes quickly. Take care.

Probably not: Every individual brain works differently. All of us have strengths and weaknesses both physically and mentally. For example, a person might understand math concepts easily but have problems with language, or vice versa. Strengths and challenges for the brain are mainly due to heredity. The trick is to learn what you like and are good at, so you can make the most of your strengths.

Common sense: If common sense actually existed, no one would be talking about it, and why? because it would truly be common, in the most fundamental sense of the word. Now, having said that, people have radically different minds, and what gets top priority and is perfectly logical to one person may completely flummox another. Not that one form of logic is better or worse that the other; they are just different.