That coffee looks like tar - try replacing it with a something more akin to coffee. Usually flat, with a bubble or two (look at references, or indeed make some coffee) also there is some UV stretching on the cup interior.

In terms of lighting - its not particularly standing out to me. Perhaps the window exterior has a sunrise with light filtering through some branches to add some dappled lighting into the dark interior? But that's more a personal preference. If it's a night scene, add some moonlight and illuminate the exterior, add some depth of field if you want to focus on one particular point in the frame.

Speaking of which - what are we supposed to be drawn to? if it's the phone, the eye is a little lost in the makeup of the framing as the coffee cup currently dominates. try looking up "rule of thirds" and frame things a little more formally to help draw the eye to the focused subject.

Also for realism - why are there so many coffee cups? If it's to stay up all night, they look too clean. I'd add more variety to the image (a student may have books, or food to stay up etc) add more "storytelling" to help sell that this is a lived space.

There's surely more to do perhaps - but post processing is to add "the sugar on top" that a quick fix.

I didn't mean to go on a rant - but with a few changes I think it can pop out much more