The $80 grocery cart I almost abandoned in aisle 7

Last Tuesday at the Kroger in Austin I had a full cart, about $80 worth, and my card got declined because I forgot to move money between accounts. I stood there sweating while the line behind me grew, so I asked the cashier to hold it and ran to the ATM across the street. That withdrawal fee was $3.50, which stung, but the real win came after: I sat in my car and sorted every receipt from the last month on my phone. Turns out I was bleeding $12 a week on energy drinks I didn't even finish, so I cut those out and now I have a $48 monthly buffer. Has anyone else had a panic moment like that turn into a tracking habit? I'm curious what little purchase you discovered was your own money leak.