This is a pretty great start, especially for your first game! I really like the ship carrying all the power-ups. Reminds me of Sinistar.
You might wanna slow down most of the asteroids and comets though. They soar on-screen really fast, and it's sometimes hard to dodge. It also means the best strategy for destroying them is blindly shooting off screen and hoping you get lucky.
Keep at it, mate! It's looking good!