no fat loss BUT excellent muscle definition

ok, kind of odd question but Im not finding an answer anywhere. Im doing Combat (LOVING IT btw). Ive lost about 2 lbs. not worried about that. I can see some very nice definition in my arms/shoulders/back/sides/and legs. Im finishing week 6 tomorrow. My problem is I still have quite a bit of fat around my middle. I know its not all going to just fall off...lol. But the results elsewhere aer amazing. I always had flappy triceps and now they are firm and nice.

I havent lost much in inches anywhere but the 'look' is much improved. in my calories needed per Combat I was at 1910. According to them I should have eaten 1800. I was stuffed and ususally dont burn as many calories as most due to medications. So i ate at 1500 cals. Im now burning more than ever (yay!) , and hungry more often so was thinking of pushing up to 1800 cals.

My question: could by body be sensing a deficit so it holds onto fat WHILE still creating the nice definition Im seeing? i feel awesome and energized and strong. any ideas?????