The art and player perspective look great here and this is a fun little experience! I agree that the attack mechanic seemed to be a little wonky so I just avoided enemies. I hadn't realized what the smaller blood tank was and didn't realize until I died the first time. A little blurb explaining that and that the ship's tank was literally in the ship would clear that up pretty quickly. I did love seeing the two tanks on the back of the player too.
Otherwise I also didn't make use of the jump button at all and craters would be a cool fix for that. A sfx for mining the crystals might be a nice touch too. Looks like one crystal always fills half the gauge but a sfx that rises in pitch could help communicate that idea too, just a thought. The game right now is really just missing music otherwise. Awesome submission!