While we may never know the answer in this case it is imperative for both to act with responsibility.
While a trainer needs to know how far to push his client and be empathetic towards their physical capabilities, patrons must know how far they can push their own bodies. If your exercise sessions are leaving you feeling drained and in pain, there is something seriously wrong.
Remember, exercise is supposed to make you feel alive and rejuvenated. The mild soreness and pain that you experience is supposed to wear off and with each progressive session your body needs to feel less tired and you must feel more energetic.