Finally fixed the freezing bug! I'm afraid I had to just completely get rid of the bubble animation that plays when you interact with your reflection, as it seems that RPGmaker's 'play movie' function doesn't like short animations being played frequently like what was happening in game
Still, I think it's worth it since this means that everyone should be able to play the game no matter what computer they have :]
Thank you for everyone who pointed out the bug to me, and feel free to let me know if you run into any other bugs and I'll patch them asap!!