Enjoyment 4/5: Gave me a couple of neat "oh!" moments including but not limited to the part at the end with the gravity.
Execution: 4/5: A little jank in the platforming and the first boss overstayed its welcome for me but besides that it felt fine.
Sensory: 3/5: Visuals were very nice. Audio was workable. Gun felt maybe a little loud, but not offensively so.
Metroidvania 5/5: Honestly really impressive for such a small scope. You did at least an approximation of a Metroidvania experience into this.
Minimalism 5/5: "A tiny Metroidvania where the entire map fits within one screen." Yep
IMO you have the talent to make something cool at larger scale. Following so I'll be sure I see it if you do!