At what point should someone go to the doctor for this type of issue?

I’m having pain in my torso area, namely where my kidneys and stomach are. I’ll explain…
I went to a party for Memorial Day, and I drank more than I usually do. I normally don’t drink much at all– maybe a glass of wine every now and then. Sunday night and into Monday morning I estimate that I had about 12 ounces of white wine. That shouldn’t be an issue, but I also made myself a mixed drink. It was cranberry juice, ginger ale, and Ciroc (vodka—I don’t even drink vodka! Don’t know what I was thinking). The weird thing is that I only put maybe an ounce of vodka in the drink, and I only took two small sips of it. I immediately felt pain in my stomach after swallowing, and I left the drink alone. I didn’t have water or anything else for a few hours after that, even though I should have.
I said I don’t drink much or often, and it’s because I’ve always been a “lightweight,” although alcohol hasn’t always affected me in this way.
On Monday, I woke up feeling drunk and horrible (after two cups of wine and a couple sips of heavily diluted vodka), and I had a small amount of pain in my stomach and back. I ignored it that day thinking it would go away. Yesterday, I had the pain in my torso all day, and it intensified throughout the day. Today, the pain is worse and more widespread. It isn’t unbearable, but I am concerned.
I’m trying to avoid going to the doctor because I cannot afford to pay what my insurance won’t cover, but what y’all think I should do?