Did I just see a ghost?! Or am I seeing things?! I don't believe in ghosts, at all, ever?

So it's a little before 1:30am, I'm playing a quiet video talking to a bunch of friends online and was on the phone with my girlfriend. I was wearing a turtle beach headset and one iPhone earbud underneath the turtle beach. Nobody was talking for maybe 5 mins then out of no where! I hear a very load thump, slam noise in my closet which is like 3 feet in front of me. I face the closet but I look to the left to my tv to game. My closet is 5 feet to the right. So I look up and see on the top self my guitar hero guitar falling from its normal spot onto its original spot?! It's hard to explain but was very visible. It looked like it fell off a higher self but there's nothing higher then it. So what did I just witness?! I saw an inanimate object move. My mom who's downstairs trying to sleep heard it, my girlfriend who was on the phone half asleep heard it and she got pissed thinking I threw something to wake her up, lol. I heard it through two sets of headphones. What just happened guys?! I saw it clear as day! I wasn't sleepy, it wasn't a shadow I just saw an inanimate object move. Everyone heard it too! I triple checked my closet. Literally nothing could have settled or shifted to make the top most object fall from thin air?! Plus nothing could shift or settle to make such a loud bang. I reenacted the noise by throwing it at the wall and it took some real force! Like enough to toss it 4-5 feet infront of me if there was no wall infront of it. Ghost, hallucination, science? Help

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