Please follow your doctor's advice. He is absolutely right.
Reasons:
1. De-rotation of a long tooth i.e canine requires a lot of time and chances of it's remaining stable in its new position are also low.
2. Jawbone at your age becomes brittle requiring more time for tooth movements.
3. Your doctor knows how your body is responding to the treatment and does what is best for you.
Next Steps
KEEP FAITH IN YOUR DENTIST
Health Tips
If you are actually unhappy with your treatment then take personal consultation with another dentist.
To expect a fair advice make it clear to your new dentist that you have come only for an opinion and not for treatment.