Thank you for only posting 1 photo for C&C.
Most often the most compelling issue with amateur photos is the use of light. Your composition is OK. I would suggest you should have gotten a bit closer.
For most people pictures having light in the eyes (window to the soul) is paramount. In this photo the eyes are dark, and most viewers will have trouble making a connection to the person.
The issue with the background is that the lens used produces a CoC that has a somewhat large diameter limit, which gives the quality of the background blur a grating, jittery, drag your fingernails across the blackboard, kind of feel.
Had strobed light been used to light the subject, the shutter speed could have been used to make the background darker making the strobe lit subject 'pop' from the background. The strobed light would have also added light to the eyes solidifying the likelyhood that viewers will connect with the subject.
I have done an edit to simulate what might have been possible had you used strobed light as I describe above. I have gotten closer (cropped t0 7:5 aspect ratio), darkened the background, added light to her from on the lens axis (like from a popup flah set to lower than full power), and added some higher quality lens blur to the background and got rid of some of the background distractions. Since it's a quick edit it is only intended to illustrate what may have been possible, not as a ready to print edit.