Is this normal behavior for my betta?

Hey! So I got my betta about a week ago now, I'm new to keeping fish so I'm probably worrying over nothing, but I like to be sure.

So
My betta, King Jeeves, tends to mostly hand around the front of his tank and sometimes push a little against the glass and stuff. This is new over the past couple of days, in the past he only came and hung around the front when I was getting ready to feed him.
He also seems to like the thermometer a lot?

I mean it might be because he's gotten used to me and, as a uni student, I'm mostly at my desk when I'm in my room and he's also on my desk, the front being right next to where I sit.
Or maybe he might be bored with his tank? I know they get bored sometimes and it's good to rearrange the tank, which I haven't done because in his tank (15 liters, approx 4 gallons I think?) is too small for the ornaments I have to sit anywhere else and look good. I had a couple of plants that I lent a friend for her betta until she gets some herself next week...

Am I over thinking this? Is hanging around the front of the tank perfectly normal??