Weird - Screen Dimming While in Use and Ribbon Showing Recording?

Weird -Ventura 13.2 mac pro, today screen started dimming several x while using to black, brought brighness up. Then ribbon showed something odd - red dot like recording, (wasn't) & apparent time notation and ‘167.47 gb’ and stop button, took snap. What the heck happened? Was NOT recording anything. Restarted immediately in case of malware and backing up - but mystified. Excuse messy keyboard!