ok, so early this morning, i went out to start my car ( 91 CRX DX ), it started, it took a little cranking to start, but i figured it was just bc of the cold weater ( -5 F), so i went back inside, and after about 10 mins i came back outside to leave only to find that the car had stopped running. so i started it again, only this time it didnt start, i cranked it a second time and it worked but as soon as i let the clutch go, it died, and thats the last time it started. i tried jumping it, getting a new battery and nothing has worked. its in a garage now, with the heat on and im going to leave it like that for the night, but im at a loss for what to do next.

any ideas??