Well, if you are going to do push-ups that much than you should split them 50/50 and not do a whole 75 at once but only 50. I am not saying you should do so much. And don't just do push-ups because then all your muscels will be in your upper body. I think everyday you should do equal amounts of calorie burning, and muscle growing excerces. A good excercise for muscle growing and calorie burning is jogging because it makes ur lower body stronger and it burns calories. Sit-ups are also good as they help your spine. Do stuff like that. Although it is also good for you to stretch your muscles after daily excercising including when you first wake up. Try not to eat too much un healthy stuff too. You are doing a nice amount of excercising but you shouldn't just do one excercise and you are doing to much excercising. I know that if you excercise too much (especially on one excercise) it can be unhealthy for you no matter what you eat. So just be careful.
Lol I'm a girl and in high school I used to do 10pull ups, 400 crunches, 100 full sit ups and 50 push-ups and 50 reverse sit ups.....I would progressively do more exercises till you reach the body you want :)