Digital painting

Find it so hard to assess whether my shadows are correct and just where exactly they should fall to keep them consistent - have had a go here on a wee pic I drew a while back and would be most grateful for any feedback. Can’t decide if I like the highlights either, the one on the face is bothering me especially but it’s the best I have so far, lol. That said I do still love my attempt so far and I guess like everything it will get easier with practice.
The class was great, will keep working on it and eagerly await any advice anyone with a more experienced eye can offer x