Also, the yellow font on red background and the saturated blue button are not good color combinations. I recommend at least using a stroke for the font and/or the buttons so that it is more separated and easier to look at if you don't want to change the colors.
It's a good attempt for a first game, but they move so fast that you can't get many before they vanish. Or at least, I can't given that I'm using my laptop's built-in touch-pad in lieu of a mouse. Also, I recommend adding a mute button in case if you don't want to listen to the song.
It just occured to me
that I've been in this fight again and again
And in the same way every time I repeatedly die
I never will give up
As I attempt to bypass my opponent's defenses
But again I'm underpowered
If I only had increased my attack spells
It would make it so much easier to beat this person
But every time, somehow
Every time, somehow
Every time, I lose
I can't defeat Silverkin
No matter how I try to block all his spells
He just kills me again
And even though I can burn him
It's no use.
I try to fight but I am killed again in the end.
I shoot as much as I can
But when I had to go against Silverkin's barrages I was helpless again
I'll try again, of course, but this is my plan
I'll keep on sending as much blasts as I can
It just occured to me
that my HP pool is almost empty again
If I don't end this fight now I will never progress
I never will give up
But it's so difficult to pass this fight
And now I see that I'm forced to click Retry