Apple Watch Screen.

So I was checking-out at Walmart about a week ago and I could hear my Apple Watch making a strange sound like something was jiggling inside of it or something. And once I got home, I was grabbing all my groceries and my screen had fallen off. I bought it from a lady who was selling it and it was working perfectly fine until this happened. I don’t have the insurance on it, because I had bought it off of someone. So I’m just wondering, should I send it to Apple for them to repair? Or is a home thing I can do to fix it. I was able to place the screen back into the watch, but I have it on the charger right now and it’s not even showing an Apple logo or the battery level or any of that. If someone could please help me, I would so grateful! Thank you so much! Whoever reads this, have a wonderful day!