Although I'm new to sobriety myself, on day 17 with no drinking, I've been offered a drink in the past few days and I've just simply responded with "No, thank you. I don't feel like it." And that's been suitable enough, no one's even really given it a second thought. It's just been kinda like "ok whatever you say" and it's no biggie. Just try what you feel most comfortable with.
Wes