Question: what are you supposed to do when you get stung by a jellyfish?
Answer: Rinse the area with vinegar. (Not cool fresh water or seawater, which could make it worse.)
Avoid rubbing the area, which also can make things worse.
Use tweezers to pull off any tentacles still on your skin. ... 
Do not put ice or ice packs on a sting. ... 
Check with your doctor.