Is it possible to make my nose less round and less upturned? (Photos)

Based on your photos, you are a good candidate for rhinoplasty. The rotation can be let down some and the columella extended again. This will be done with cartilage grafts. At the same time, we can try to make the tip thinner as well, all while keeping it looking natural. Be sure to see a rhinoplasty expert for consultation.

Unfortunately you have reasons to be upset, it is evident the very poor quality work on your nose, some key points:
-over scooped dorsum, with total bridge collapse, saddle deformity, etc
-massive over shortening of the nose, with likely aggressive caudal septum resection
-columella tucked in, likely with a tongue-in-groove maneuver that was unsuited
-boxy tip with verticalized lateral cruras that has been untreated

So in general a massive over resection of structures without any structural maneuver worthing mention or noticeable, making you very close to a pure asian nose, and thus has to be managed, in the same technical strategy than asian rhinoplasties:
-rib grafting to restore the dorsum
-a dorsocolumelar grafting (mallet shape) is likely due to restore doral height and tip length at the same time
-tip revision in full

Do research very well by dozens of in person and online consultations, do not accept any small or conservative procedure, fillers, etc, go only for comprehensive surgical plans involving the restoration of the nasal structures that have been massively extracted, giving them a desired shape.

In the associated link you can see information and B&A images of your problem.

Hello and thank you for your question. Based on your photographs, you are a great candidate for a revision rhinoplasty. Maneuvers for your surgery would include release of scar tissue, placement of extended spreader grafts to derotate the tip, among other maneuvers. With good surgical technique, you could have an outstanding result. I recommend that you seek consultation with a qualified board-certified rhinoplasty surgeon who can evaluate you in person.

Best wishes and good luck.

Richard G. Reish, M.D.
Harvard-trained plastic surgeon