Needle not moving. The needle on my Sew Smart is not moving up and down. I popped off the side

Question

The needle on my Sew Smart is not moving up and down. I popped off the side cover and it's not attached to anything. You can move it up and down with your fingers. There are a couple of pcs. that are made of metal that are in the attachments box. One is rectangular with a hole and a tightening s***w in the hole and the other is is round and about the size of a quarter. I think they came out of this machine.