My urine smells concentrated. what is the problem?

Please clarify: There is no medical condition or diagnosis for "urine smelling concentrated". What does that mean to you and what worries you about it?

Dehydration: Do you mean a heavy "urine" odor, or that of an infection? If your urine is dark yellow/amber, but is otherwise "clear" (no sediment/"cloudiness"), then you are probably "dehydrated." a foul odor would suggest an infection. Many individuals are chronically dehydrated which results in frequent infections or stone disease - adequate hydration results in a urine output of > 2000 mls of urine/day.