Fin Rot?

Fiona Lawrence asked 5 months ago

I just got 2 betta fish last week with my girlfriend. We keep them seperately like you should, and one of them is doing marvelous despite being a tad shy.
But my fish, Merlin, I’m worried about.  yesterday I fed him 2 pellets being going to work and when I came home 6 hours later, he was acting sluggish and didn’t come meet me at the front of the tank like usual or follow my finger around. So I let him be but watched him for 5 maybe 10 minutes. He then swan to the middle of the tank, and puked. It looked mostly digested. There were no white parasite looking things, and ordinarily he swims around happily. I thought maybe I fed him too much, since he’s still not an adult, but I think he would’ve puked before 6 hours.
So I started researching things that can be wrong with a betta fish, and i came across fin rot. So now I’m very worried. He’s still young, so I can’t even tell what type of betta he is. But his tail looks kinda raggedy. I’m new to this do idk if he has minor fin rot, or if he’s just a young crown or comb tail maybe. I’ve included pictures below.
I love this little dude already so any help given would be great.