Did lifting a 6 pound bowling ball, three weeks after rhinoplasty ruin my long term results?

I
don’t think that lifting a bowling ball will “ruin” your long-term surgical
outcome based on the information you provided.
It is best to follow your surgeon’s activity recommendations to heal the
best and improve your surgical results.
Of course you should check with your board certified plastic surgeon for
their opinion.

Doubt this has any effect on your long term result but can perpetuate  short term swelling.  Be sure and check with your surgeon to be reminded of their protocol for  a successful outcome.

Unless you hit your nose with the ball it is very unlikely that bowling at. 3 weeks will have any long or short term affect on your noseDr Corbin

I can't think of any reason how bowling at 3 weeks post-op can affect your nose except for a possible minor tension on the alarplasty scar (if you have it) due to excursion of the alar wing during exertion.

I do not think that you ruined your long term result. You had a major surgery to your nose and it is best to air on the safe side. You are still early in the healing stage. Best to to have it checked out by your surgeon for proper evaluation and advice.