Congrats on your first game! This is really good for a first game ever!!
You nailed the NES aesthetic, the soundtrack was great, and sound design was also spot on. The enemy patterns were actually really interesting, especially with the full 360 circle path you can take to dodge them.
As you'll see in my playthrough below, I really struggled though. I only managed to reach the first boss in one run. The main thing was not being able to predict when an enemy was going to spawn at the edge of the screen, so I got hit from behind quite a few times.
A few other minor bugs I noticed after watching my recording again: When I first played the game I start with 5 health, but then in subsequent retries I spawn with just 3 health. Also as you'll see the high score game over screen was only showing 0 points
Nice work! I had fun playing :)