What do I do? I have a DVD stuck in the player?

I put a movie in, didn't like it. But now, I noticed the DVD was still playing. I went to open it and the DVD slot was empty. It starts to play whenever I close but the slot is always empty when I open it. I've tried tapping it and shaking it but nothing works. It would be alright if the DVD was actually mine, but it's not my DVD, it's the libraries and it's due back in almost two weeks. What should I do?
 
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