Do you also check for TAB below the lesson? Usually chord diagrams can be found there. There's nothing wrong though with just pausing the video like you're doing, and figuring out what exactly the chord shape is... working it out like that helps cement it in your memory! Make sure you know all the chords for any given lesson... when I took the fingerpicking course, I would usually first watch the whole lesson through without playing the guitar. If Lisa says "this song is going to use the chords Am, F, C, G and Em.." I would make sure I knew how to fret those chords properly before proceeding with the lesson. Divide and conquer. Keep at it! :)