When i get nervous and scared i start to urinate clear urine in mass amounts and get dehydrated?

See below: Usually, when one experiences anxiety or fear, their 'sympathetic' (fight or flight response), as opposed to 'parasympathetic', part of their peripheral nervous system is stimulated. This usually causes urinary urgency, frequency, and sometimes loss of bladder control but usually causes decreased urine production by the kidney rather than increased (diuresis) as you describe. Exceptions occur.