Thanks for playing and streaming it!
I did arrive to your stream during your play and saw most of it live. Just didn't want to say anything to jinx your playthrough :).
You got him down to 4% the second try and blew yourself up at the last one... Yeah the boss needs 50 hits to be destroyed but since you can spam bombs he can be defeated fairly quickly once you get the hang of it. The shop gives you options to change your tactics if you want so if low on bombs you can skip the other power-ups and add another 60 bombs if you want to.
I changed the boss fight several times trying to get it to a sweet spot during development. Its really hard to get it to fit everyone. I initially had the boss retain the same health level at player death, but that didn't feel right so I changed it.
There is a minimap in the game, you just have to find it.
Thanks!