"VDO" light blinking
 

First question is what's the purpose of the "VDO!" and what does it mean.
Secondly, my VDO light was blinking intermittently this morning and the car started acting sluggish. I know whenever one makes a quick takeoff etc, it'll blink, but I was driving normally and it started blinking for about 5 minutes or so. My fuel light cause I needed gas, so once I got gas, it stopped blinking.

But, it's still driving a bit sluggish at times.

ANY help will be appreciated.