It'll probably be alright tomorrow. From [How does accepting an answer work][1] on Meta Stack Overflow:

> - The accept rate is heavily cached and can take 24 hours or more to update.

There are also a number of things that do not count towards the accept rate calculation.

> **Which questions do not affect the accept rate?**
> 
> - Community Wiki questions
> - Closed questions
> - Questions with no answers

  [1]: http://meta.stackoverflow.com/questions/5234/how-does-accepting-an-answer-work/5235#5235