What happened to my Explorer it just died...no joke?

[kobe_mvp_81]

I just bought a 1998 Explorer Sport 4x4 about two weeks ago. My overdrive off light flashes every once in awhile I read in the owners manual that that means it just needs to be serviced so no big deal there. About four days ago the check engine light came on and that worried me although when I bought it the previous owner said there's a possible clogged catalytic converter or an o2 sensor going bad that's why the light comes on but it'll run. Im in college so money is tight that's why these haven't been replaced yet. Anyway the day it died the check engine light was on, the overdrive off light was flashing, then the lights dimmed a bit only to brighten up again, the battery light came on and the check gage light came on which in the owners manual it says that just means gas is low and I have plenty of gas. When I tried to hit the brake it was tight and the power steering went out. I pulled over and shut it off thinking it would just start up again...it didn't it turns over but makes a weird noise and doesn't start. A mechanic said timing chain or belt whatever it has because he looked in I guess it was the engine oil and a rocker wasn't moving. I was just wondering if anyone has had this happen or knows what the case is? Any and all feedback is appreciated.

Thanks!