How do i no if the stinger is out from a bee sting?

Easy to see: When stung, the bee actually leaves the stinger behind attached to the venom gland. Scraping it sideways to prevent squeezing more venom into the wound is recommended. If you don't see a gland attached it is either out or you were stung by something else.

Check visually: You can usually see if the stinger remains in you skin. Remove stinger by scraping along edge of skin with a credit card. Clean with soap & warm water. Apply ice in 10 minute increments; alternating 10 on & 10 off. Tylenol, aspirin or Motrin for pain or Benadryl for swelling. Make a paste of 2 parts baking soda & 1 part water & apply. Throat, airway or tongue swelling – call 911.