WTF is wrong with my metabolism?

Okay, this is freakin absurd. I'm a pretty healthy person overall, I'm 5'11 and I'm hovering around 180-184 pounds right now with about 15% body fat. My max lifts are bench 225, squat 275 and dead 315. I'm 18 right now, ive always been an athlete and ive always been strong. At around 14 years old a time when my parents were going through a divorce and with the stress of school i let my eating go out of control and just lifted super heavy for a few years doing what could be perceived as a huge dirty bulk. At 16 i went to the doctor and my blood pressure was like 160/130 i had dangerously high cholesterol, poor functioning fatty liver, and i was weighing about 240 pounds at 5'10 with around 22% body fat. I've come a long way from there dropping about 55 pounds of fat and retaining the muscle i accrued over that depressing stretch of my life. I have been at my current status for a bit now and am looking to cut. I was weighing about 195 not too long ago and have cut about 10-15 pounds. My goal right now is a lean muscular 170 at about 10% body fat. I've been great, lifting and doing cardio and really watching my diet, and ive been loving my results, but today just got to me, and i dont know if im looking for advice or just venting but, the deal is, i woke up weighed myself at the usual time after morning urination, and i was 181. A great weight, i was very happy. I ate very clean all day, some muscle milk, eggs, nuts, banana, apple, chicken, beef jerky. it all probably totaled to about 1700 calories. My workout for the day burnt me 2000 calories. HOWEVER, even though i ate below maintenance, and should be on track to lose or maintain weight at the very least without burning 2000 EXTRA CALORIES, lifting and doing HIIT, i gain 3 pounds. not only was the food clean, but it was below maintenance AND i burned 2000 ****** calories. I know that yall are bout to call me crazy preaching water weight n all, and i know it, ive done this enough and been around fitness long enough that i know if i just stick to my diet and workouts it'll all come off in due time, im just frustrated! Really god damn crazy how my body does this to me. I hold on to weight so easy. I bulked in the summer going from 9th to 10th grade, and went from 185 to 245 in those 2.5 months. my total weight gain from 8th to 10th was from 144, when i decided i wanna be the strongest man on earth, to 245. 100 pounds in two years. So cutting is definitely a challenge for me since i put on muscle and fat so easily. i feel like if i eat 2000 calories which should be well below maintenance for me and i dont work out, that i'll put on 2 lbs a day. F*** man...