Why is my Nose So Wide After Septorhinoplasty? Will This Change or is It Ruined Forever?

From your post I take it you are a week out of surgery because that is when most of us remove splints. If that is the case don't even think about worrying about how things look because swelling will not go down for a few months to a year. Spreader grafts can make the nose look a little wider but you would in no way see this now. There is simply too much swelling at this point. The swelling will get worse before it gets better. In 6 months or so you will really begin to have a better idea of how thins will look. Hang in there. Give it time.

The nose can appear wider after hump reduction unless the nose is fractured and narrowed in such a way as to conteract the effect after the reduced hump. Think of it as taking the top off of the letter A. The spreader graft is also a technique which will hold open the internal nasal valve and potentially widen the bridge. We don't know what was done, and one week is too soon to tell. We hope your thin nose was part of the plan.

One week and counting the seconds.  Spreader Grafts do indeed widen the mid-nose and this may be your chief concern.  However, "time" will likely improve your overall result (be patient), you only have 358 days left for your full healing result.