How was it running? Any other issues with the motor? How many hours? There are a few different things it could be. Burning excessive oil, oil getting past rings, etc. It may just be the that new oil you put in her. I would probably start by first draining that oil out and filling it back up with the stuff you were running before or another fully synthetic 10/40 or 15/50. I wouldn’t go heavier than 20/50. Another option is a good semi synthetic diesel oil like Rotella T4 15/40. Change oil and run it and see if that fixes the smoke issue. If not, then do a compression and or a leak/down test on the motor.
If you are truly worried that your motor is damaged then do the compression and leak down test first.
Check out the link below. It may help you out also.