Gina -- glad you checked in. We've all been there. I've relapsed literally hundreds of times.
Put the brakes on. Pour out anything you've got left. Drink a bunch of water. Take a long shower. Eat something if you haven't already. Those things will minimize the hangover somewhat. You haven't lost what you've done over the last 2+ months, you just took a temporary step back. You can't change what happened today but you don't have to make it worse by continuing on with the drinking. Get right back on the wagon with us.
We're here for you.
P.S. Congrats on getting a car. Use that as an example of the positives that have come from your summer of sobriety. Don't beat yourself up, just start moving forward again with us please.