If you are having any trouble with the class missions at all then 100% you are the problem and not your class. You should be able to basic attack your way through that.
Yes lol, if you have your companion set to heals there isnt really any excuse for dying even once from a class mission other than being bad. Which isnt a bad thing btw, class content is what you do when you first start the game so it's fine to not be the best player when you do it but don't try and blame it on your class or the 5% less damage it does after a nerf.