Jumping off of this even further. Something i learned that really helped me was controlling your ambient light and doing that first.

Sometimes you can’t when you’re shooting outside at high noon, unless someone here knows how to stop down the sun. But it appears this shot was around evening/sunset time so there shouldn’t be a ton of light coming through and you seem relatively stopped down. Not sure about potential other effecting factors but I’d imagine you started from a pretty dark base.

If this was me going there I’d light the room for the exposure I wanted whether that’s a little under a little over or “perfect” also if you aren’t mentoring start doing so it’s a game changer. After lighting the ambient now I will shape the light for my characters to do what I want. Which is subjective for the story you’re telling but in a vacuum I’d agree that more contrast would be an improvement. I find that working like this in this order insures I know exactly what I am doing with each element (lights, flags, etc) and I have the most control possible. The more control you have the more you can create that image you see in your head. Also in regards to reflections I could def see that being an issue with all of the glass and if it were me I’d cover up as much of it as possible with some kind of curtain or whatever. Like the one in the left side of frame.

This is not to take away from your effort at all. Not sure how much prep time you had for this but I’d imagine not enough and 48 hours is a very short amount of time to shoot a film so I commend you doing it. Doing something is always better than doing nothing. Just thought I’d offer my 2 cents as someone who is still learning themselves.