There is nothing to worry if you have started working out 2 weeks after FUE provided you are not doing it in extreme sunshine.
I advise all of my patients that had FUE, that they can return to full work within 2 days after a hair transplant. For those that had a strip surgery, they can go to work within 2 days as well, but they can not lift more than 50 pound for 6 weeks. Working out is fine provided that you do not strain your neck muscles (Trapezius muscle). You can run a marathon if you wish within 2 days provided that there is no swelling or bleeding.
Be sure to run this by your surgeon as it's always a good idea to follow his or her advice. There may be a particular reason why a delay is important for your particular situation.
The main issues with regard to exercise is preventing sudden changes in blood pressure that could affect the grafts. For patients who had follicular unit extraction procedures (FUE), I advise return to light cardiovascular activity at day 8 and light weights at day 11. Heavy weights at day 14.
For patients who had strip surgery (FUSS), I advise return to lightcardiovascular activity at day 12 and light weights at day 15. Heavy weights at day 21. The main issue with FUSS type procedures is proper healing of the donor site.
It really depends what you did during your workouts. In the extreme, if you did anything to physically disrupt the grafts then you would be running the risk of poor growth. On the other hand, light exercise like walking or only partially exerting yourself should not be a problem.
Light work out after two weeks of hair transplant is alright . However for heavy work out it is best to wait three weeks.
It is always a good idea to follow your doctor's advice. If you are worried something went wrong, it is also a good idea to follow up with your doctor. The mistake is not following your doctor's instructions. Exercise has nothing to do with a failed hair transplant.