When to work out with sore muscles

I am a beginner to these types of workouts, and I am having trouble judging when I should push through with sore muscles, and when I should take a rest day or an easier workout.

I had been picking my own videos from among the level 2 videos, so I would choose something that did not work whatever was sore. However, I just started the Low Impact Round 2, and there are several scheduled workouts in a row that work the upper back, which is a weak point for me.