Congrats on breaking your competitive boxing virginity!
A loss by decision is not bad - especially for your first fight. I lost a few of my initial fights but learned so much from those losses. I think you usually learn a lot more from a loss than a win.
You may easily win fighting him again in the future now you and your coach have seen what he does. You'll be ready for him but he won't be ready for the improved you. :)
That's how it's worked for me so far. I'm still a baby in the sport and still have a lot of improving to do but my first 5 fights did not even begin to show my potential - win or loss they were just for learning.
You are right to still feel good despite not getting a win - don't let anyone tell you different.
