Hi guys

I need some help desperately. I have a flight in six hours and had some diazepam prescribed to help with severe anxiety/panic disorder. Being the stupid idiot I am, I bought a beer at the hotel bar just now and had one sip before realising that you can't mix diazepam and alcohol. I haven't taken diazepam yet, but I need it desperately for the flight. Will one sip of beer six hours before I take it have awful effects? I'm terrified.

Absolutely banging my head against a wall right now. Can one tiny little sip kill me?