Did I gain muscle or fat?

Hi! I am 14 years old, now 127lbs. and im 5 ft 6 in. i used to be 123lbs, but i recently added about 20 more grams of protein to my diet of about 1850-1900 calories. i am a jogger and jog 14 miles weekly. i am asking the question because it seems as of when i started eating more protein, my stomach got a little bloated looking, but it was hard, not flabby. So because i started eating more protein, did i gain hard muscle in my stomch? THANKS!!!!!!!