I Fudged the Mileage on My Car Pool Form

So I've been part of this carpool for months now with my coworkers, and it's been great. But lately, gas prices have just been through the roof. So when our manager asked us to submit mileage logs to get some reimbursement back, well... let’s say I was feeling a bit less honest than usual. I added an extra mile or two each day to make up for a weekend trip that had nothing to do with work but needed gas money somehow. Now every time I look at my carpool spreadsheet, I feel like there's this little voice whispering, 'You didn't really go those extra miles,' and it's driving me crazy. It was just a couple of dollars each day, but the guilt keeps building up. I swear next month I'll be more truthful, I promise.