Questions: Health & Fitness

im a pre diabetic teen which i found out back in December so my doctor said to watch food intake espiecally unhealthy carbs like bread, candy, etc. and provide more exercise , i exercise almost everyday since i have pe which is an hour everyday, we either play sports , walk around the track and every week run a 15 min mile and bleachers for 15 mins and i walk home to provide more exercise sometimes run on the treadmill or lift some weights i still eat some sugary stuff (i completely cut out soda and hardly ever drink juice , water is all that i drink) but i lessened it a lot more than what i used to eat before i found out i was prediabetic and lets say i eat a piece of chocolate cake i walked it off after so in June i have to go back to my doctors to check my sugar to see if i have diabetes or still on the borderline of it, the thing is i lose weight but then gain it back and lose it and gain back it is those 5 pounds that i lose (im not talking like 20 lbs gained, im only 10-15 pounds overweight) i always lose 5 then gain it back so the real question is will i still get diabetes even if im exercising and trying to eat healthier?

im so fucken scared but its extremely hard being pre diabetic as a teen who are best known for eating junk food. i have a feeling that im already diabetic :(, please comment below and say your opinions , i really need your help.