3g is a little excessive, 2 is a better number if you have trouble downing lots of protein. 1.5g as an absolute minimum.
Control your calories, eat when you want and stick to your minimum macro numbers for fat and protein and train with weights to preserve muscle mass. Keep it simple and keep track fortnighly of your weight/BF etc.
Watch out for the usual excessive exercise energy expenditure. Use walks and a little cardio if you want to eat a little more food the than 2100 cals.
Good luck.