I by accident missed my appointment with my doctor. I called to reschedule and apologise. he said he would only reschedule if i compensate him for the visit i missed. If i decided not to reschedule would i be obligated to compensate him?

You are obligated to compensate the doctor for the revenue he lost by your forgetting the appointment. Had you not booked the appointment, he would have taken another patient who would have paid him. Compensation is slightly less than the price of a kept appointment because as a result of your no-show he had a few minutes of rest (Shulchan Aruch Choshen Mishpat 333 1-2).