Oh, been there! I promised a friend a crocheted afghan for their wedding gift. I chose a pattern and style I'd never done before (big mistake.) It was crocheted, and then had a cross-stitch pattern on top of that!
I did get it done. But the last 2 days before the wedding all I did was crochet - 10 hours a day!
Now, I promise nothing. I use the "I hope to finish it by..." instead. :)