What I see here is that they lacked expression, or just lacked some additional atmosphere to support the feelings they are showing.
For the panel you said the girl seems shockd rather than fear, You could do it like this. Widen the eye, and male the iris a bit smaller. Add some sweat drops on her face and make some squiggly lines like ~~~ around her body (couldn't draw to show you since its already 1 am, so sorry).
One way I could suggest is that you take a mirror, Make expression, exaggerated them, and draw it from here. That's the easiest way, I think.
Also, make different angles from what you have right now. Either it's from top to bottom, from bottom to top, etc. a very dramatic close up to their face will also be good. Like a panel solely for their eyes. If you draw them right, that could already convey a lot of emotions.
I don't think these were that helpful but this is some old pages I made some years ago (they are sketchy as f plus made on a lined papers and I never made it public yet), but you can see that eyes convey a lot of emotions here :
Using my own drawing might bit be the best way to convey it, and I'm not that good with explaining but I hope you got what I mean.