Assuming you're in class, tell the teacher. In real life, put a lot of pressure on it using a clean cloth. Put the cloth where it's bleeding and apply firm pressure. When the cloth has been soaked through, simply place another clean one on top. DO NOT REMOVE THE DIRTY ONE. Stay calm, and ask for help. Do NOT remove the gloves, as doing so may cause more harm than already done.
Hope that helped! :)
Have a wonderful day! :)
DISCLAIMER: ALWAYS check with a reliable source! Don't cheat!