Can you get an eyelash behind an eyeball?

No: You can get an eyelash stuck underneath your eyelid, but there is no way an eyelash can get behind your eyeball.

No: It can get deep under the eyelid but can't get behind the eyeball itself.

No: The front of the eye is completely isolated from the tissues behind the eye by a continuous layer of conjunctiva. You cannot get an eyelash behind the eye unless there is a traumatic break in this lining.