thrown rod maybe?

Okay, so today I was making a 1 hour trip with my wife, when she heard a noise coming from the engine. It sounding like a clacking and the higher the rpms the faster the noise went. then we pulled over and our car started to overheat. so we let it cool for about 15 minutes and then we began to put water in it. But for that first 15 minutes, the water boiled nonstop in the reservoir, and then we noticed that when we were putting water into it, that the water was completely leaking out. So then we started to put it directly into the radiator and noticed that there were brown flakes in it. Which I know normally means a cracked head, but those have been in there for over 8 months and we were told by a mechanic that it was rust, but since this happened, I am skeptical. So I need to know what happened to my car. I have a 95 plymouth neon sohc.