Yeah, you're supposed to send them over to the service desk.
When you change a price and mark it as 'Guest Price Challange', the item drops into something called 'Price Audit', where someone goes around to all the locations for every item that had its price changed to try and figure out why (old sign, in the wrong spot, etc). If it's a large price difference, the LOD is also notified. If they can't find a reason for a price change, it could reflect badly on you.
No worries, just be sure to send guests to the service desk in the future for price matching. You may also let your GSA/GSTL know, but if they haven't said anything I wouldn't worry too much about it.