Thanks so much for the Bug Report, we will be working on that as soon as possible! This boss has been the biggest game crashing issue all development long lmao
Also, there is an indicator of your life! When you get hit, the ship flashes white and its color changes to yellow or red. It also looks progressively more damaged.
UI has been a difficult thing, since I wanted to keep the screen as UI/HUD free as possible to make it more immersive.