Amazing game, my dude, I loved every second of it. The using-your-HP-as-projectiles is genuinely one of the most unique mechanics I've ever seen in a video game. Your world design is top notch and exploration felt super rewarding.
Only thing that I really wished for is an ingame map - would have made traversing the whole dungeon much easier. If you ever decide to work on this game a little bit more, a map would be the best QoL improvement any player could ever ask for!
(Also maybe an upgrade towards the end to reveal all missing collectibles on the ingame map - both times I've completed the game, I've finished with exactly 350 coins remaining, needing 400 to buy that last heart piece and it's been eating at me.)
Regardless, I really hope you work on more metroidvanias in the future - you're an extremely talented developer and I've fully enjoyed Blood Pressure!