Why do I have a line on the left side of my nose? Is it from narrowing too much? (Photo)

I like your profile too.  The photos that you have provided are difficult to assess, however, they appear to show that line on the profile view that you are referring to is present on the preoperative view as well.  If your surgeon broke the bones on the sides of your nose, then it is possible that your nose is now more narrow on front view and the indentation is more apparent.  Three weeks is a very short period of time, but during your follow up visits you will be able to see if the narrowing is too dramatic and the line becomes more obvious requiring revision surgery.

You are only 3 weeks from the surgery and it is usually recommended to wait at least 6 months to allow for healing and resolution of any swelling.However, you appear to have a narrow bridge with the L side being more depressed than the R side.  The tip also appears to be slightly wide. The profile view looks good.I would discuss these concerns with your surgeon.  It may be that your nose can have some "enhancement" with fillers after complete healing has occurred.

What you are seeing is shadowing on the nose from where the nasal bones were narrowed. This could partially be due to swelling as you are only three weeks postop and likely have a considerable amount of swelling throughout the nose. Be patient during this process and make sure you have adequate followup with your rhinoplasty surgeon to monitor the nose for changes and also address any concerns along the way. Best of luck.