Hey, it's kinda Spacer Harrier! I like the concept of shooting delaying the health coming in. Maybe there should be other trade offs around that, like enemy projectiles homing better or moving faster.
Feels fairly polished, but there were a few things I think could use a little work. The moon makes some enemies a little hard to see, so maybe moving that off to the side would help. The shooting sound effect kind of grates over time, maybe make it quieter/or modulate it a bit. The main thing is that the difficulty is a little on the easy side. I think maybe the health-giving enemies show up too often or give too much health. Either way, I never felt in danger.
A little polish and a little more variety, and I think this would be a great game!