flashing cel

I was running late, so I started with some quick shifts and high revs right out of a cold start, then a stop and a quick u-turn. Within sixty seconds (right after the u-turn) I noticed that my acceleration had gone from peppy to pathetic. I drove about 40 miles and went from 1/2 a tank to 1/4...

I turned my MSP on today to discover that it was idling very rough and uneven, and the check engine light is flashing. I'd just ordered and received my timing belt components in the mail and was going to replace the whole thing in a few days - I really hope my timing belt didn't fail just now...