Shouldn't be a crisis. We hope you took the cake right out of the oven. It may be a little drier than you'd like. When you took it out of the cake pan, did the bottom or bottom edges seem burned? You might be able to trim off any overdone portion with a serrated knife. You could spread a little apricot glaze between layers (if it's a layer cake) to add a little moisture and a bit more flavor. You could also brush a little orange juice onto the bottom of a layer if the flavor will be compatible with the cake and frosting/glaze.

A lot of ovens are not very well regulated anyway - you might be baking things 25 degrees lower than you should all the time, and tonight you just hit the nail on the head… (an oven thermometer will settle that question).