I have been wearing contacts for about 18 years and I am ashamed to say I don't care for them regularly so I have had that happen to me quite a bit.I did call my eye doctor and they said you have a membrane around your eye that prevents things from getting behind it.If it's in there it probably just caught suction on the eye in the lid,you would feel something,sometimes putting eye drops in helps release it.It's just a good chance you rubbed it out without realizing it and it may have dried up and shattered(depending on how long your nap was).I'm sure you're fine,just keep and eye on it(no pun intended,LOL)

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