Congrats on the project! The bloom effects on the orbs and the sound they make are cool!
Here are some feedbacks and problems I faced
I think there is a bug on the movement. You move very slowly until you press shift to run, after that you keep running for a while? I didn't really understand and felt a bit wrong
It would be helpful to show something in the HUD about the other weapon, I was shooting rings for a while until I decided to read the game description to find the tutorial there. After discovering the vacuum gun I started to make some progress. An Icon in the hud with a [tab] label would solve this problem.
The game is a bit hard to read, when the ghosts stabilizes, they close their eyes, but when they are facing the other direction the eye is not visible also, so these two situations are visually similar, making the game frustrating at times
After dying, I couldn't click the Menu button. I think the mouse was still locked from the FPS logic and the Menu button was not selected, so Enter or Space didn't do anything
Hope it helps :)