Can't figure out!

My 2000 dodge neon is about to be burned! I recently experienced my timing belt snapping on me and I replaced it plus the head and a sensor. It sounds like a dying lawn mower and shakes and turns off if you don't keep your foot on the gas. I have tried over and over thinking that my timing points are off just by a hair, could this be the problem? Or is it because the trouble code has not been erased? I don't know, I honestly cannot figure this out, I have torn my engine completely out over and over replacing parts and putting it all back together and I just can't do it and I'm ready to just call it quits. Please, my caddillac is draining me when I take my kids to school and for work and I need my other car to run! Any help is greatly appreciated not only cuz my car may start and work properly but it gives me just that much more knowledge as a woman who works on her own car! Thanx!
Engine is 2.0
Standard
SE type not sports
4 door
2 wheel drive