I stand at work for a long time every day, and there are many little red dot on my legs, like bleeding spots, which gradually disappear during the rest.
It should be because of standing for a long time that some tissues are congested. Don't worry too much. It is normal. It's like working out. You have been doing push-ups. You need a rest to do better. I know a little about this. You can massage your leg muscles at any time and pat those places where you come from little red dot. Take time to be lazy when you should be lazy.