If you can add a close-up photo of it, that would be excellent. Until then, I'll assume there is at least a millimeter sticking out. If so, try grabbing that with needle-nose pliers.
If that fails, you could CAREFULLY put a dot of Super Glue on the tip of a straightened paperclip. Press that against the headphone jackplug ONLY. Hold it very, very still for 10-20 seconds. If it dried correctly (fingers crossed!) you may be able to slowly draw out the end of the plug by pulling on the paperclip. (DON'T get it stuck to anything except the plug you're trying to remove!)