Audio Playback is not Working

I have been working on this score for my University portfolio, and the other night I fell asleep with it open on my laptop, which was on my knees. I woke up in the morning to find that it had fallen to the ground. I am still able to access all scores and in every other of my scores the playback is fine, so I'm wondering if it's something I clicked in my sleep in this specific score? Any help would be appreciated thanks, as my deadline is coming up soon!