Wedding 5 days before missed period - what to do?

Ill be with all my high school friends and want to have some drinks as I never see them. I'll be 9dpo so I plan on taking a frer in the morning but if it's negative i realize there could still be a chance of pregnancy and I couldn't live with myself if a few days later it was positive and I had drank a lot at the wedding. We had a lot of sex during my fertile week including day before and day of ovulation so the chance is there. 
What would you do? Just have a few drinks? (Of course if it was negative the morning of the wedding/9dpo)