What does it mean when my wrist hurts when i let my arm go loose?

Not specific: This is not particularly indicative of any specific condition but that doesn't mean that something is still not wrong. You will need an exam to evaluate the possible causes of the pain including arthritis, sprain, strain, ligamentous, tendinous injury, etc.

Need more info: Wrist pain can be caused by many issues, traumatic or atraumatic. Best to get evaluated by a physician so a more specific diagnosis can be determined.