Drooping on lower right side after rhinoplasty. Could this be ptosis and what are my options? 5 years post op. (photo)

Nerve and muscle responsible for eyelid ptosis are located within the orbit and far away from rhinoplasty surgery field. It is unlikely that rhinoplasty was the cause of ptosis. It would be best to seek a consultation of a board certified plastic or oculoplastic surgeon in this regard. Good luck.

Sagging of the lower eyelid is referred to "lower eyelid retraction". It is very unlikely that rhinoplasty surgery caused this. Unfortunately, your photo is not ideal: you are looking down into the screen so your lid position cannot be evaluated. Re-take the photo with looking directly into camera lens, rather than your phone's screen. If you do have lower eyelid retraction, this can be improved with surgery. I would recommend seeing an Oculofacial plastic surgeon (Oculoplastics).