High Protein Shake when trying to lose weight??

RNWall

Over the past few days I have really started working out A LOT more than I was before. I am now finding that I am netting in the 300s for calories per day. I know this isn't good but I can't eat any more during the day than I already am (due to work and just not being hungry) and I by the time I get home its pretty late and I don't want to fix a big meal. Is drinking a high protein shake from the gym (450-600 cals) doing more harm than good in my weightloss journey? Any comments appreciated my diary is open. BTW- I am doing cardio as my workout but I am starting weight training next Monday 3x a week with a trainer.