Good premise, I think you have the core idea of what you want to do - and the execution is pretty solid. Movement control also feels good.
What I think you can improve the most is polish, especially the UI - for me a lot of the smaller things made it hard for me to immerse myself in the game. To give you an example, the placement and the quality of the images, the lack of visual output for the gun, and the font all don't quite fit the rest of the assets (the robot and the environment setting- btw I think these game assets are pretty good).
Other than that, I really think you've put up something decent in terms of gameplay and game design. Good job!