Google is testing showing the last time you viewed an ad, a Google Local Service Ad, by adding a label with those details. In this case, Google is showing "You viewed 15 minutes ago" next to this ad.
Anthony Higman spotted this and posted a very low res screenshot of it on X - here it is:
We've seen Google do similar labels before, including you visit often labels. If you actually visited a local business, you recently viewed in the local panel, and more that I cannot find right now.
Forum discussion at X.
