She is looking alright. Her first "real" leaves are little more than cotyledon. Yellowing and eventual loss is expected. Basically her larger leaves are out performing her primary leaves, and they are shutting down as a result.
No that is not nute burn. That looks more like mechanical damage and some drying out. I cannot see any signs of animal damage.
Remember, we are only here to guide her, feed her, and help her when needed. Generally we are observers, and can only influence very little.
Also, just starting off sucks. We've all been there and most of our first harvests sucked. I know mine did. Im on my 3rd&4th grows staggered about 6 weeks apart and am set tto have my best havrest yet.