So then your action is too high. Might not have anything to do with the neck/truss rod. Without knowing what type of guitar you have, how high the strings are, not being able to look at the neck, ect.....we really can't give you a specific answer on your issue. It's like asking, "How do I know if my cars transmission needs work. The car drives really hard". Extremely broad question for a problem that has many different variables.

Google around for how to lower your action and see if that helps your problem.