I have done the same. Too many times to admit to. Yes, it will shrink different than the rest of the fabric. Maybe not as bad as you expect. Chances are that you will not notice it once the quilt is washed and loved. Unless you are putting the quilt in a quilt show, I would not worry too much about it. Just watch to see how it turns out and whether you can live with it the next time it happens. Welcome to the wonderful world of quilting. Hope you find this bug is a very hard one to get rid of.