This is Dr. Christian. Welcome to JustAnswer. Try holding an ice pack on the area to numb it and reduce swelling then you can pull the head out with a tweezers. You may have to dig a little bit to get at the head and pull it out. If you are still unable to get it out you can have your vet's office pull the head. Some triple antibiotic applied to the area will help with infection. If you have more questions please let me know.