Hi misspinkcat
Firstly you need to forget it and move on, it is just one slip. Many of us have had little blips and not let it hinder the CD journey.
However, and this is the stern stuff, there has been some threads here about how you shouldn't mix alcohol and CD. If I was technical I'd find it for you -maybe you can do a search.
But back to the main theme here, don't worry, you are only human, drink plenty of water and good luck for your first weigh-in, you have done well since starting x