If the clear liquid stops dripping from your nose after 20 to 30 minutes or less then it's likely just your nose clearing out any irritants but if it continue you should see a doctor because it could be something as serious as cerebrospinal fluid (CSF) that is a leak through a break in the lining of the brain.
Also known as brain leakage which needs medical attention as soon as possible.
If you're unsure it's best to see a doctor or go the emergency room just to be safe.