Betta is fiestier than usual

Question
Hello!
I've had my betta fish for a week, and he's been doing great so far. He's built himself a bubble nest, not that I'm going to breed him, and he's rather active.
Tonight I came in only to see that he was circling the outside of the tank, crashing into the walls, rather slowly, then going to the other side and repeating. I tried distracting him a little with a mirror or bright colored objects outside of the tank, and that didn't work so much.
About 20 minutes later, he's seems to be more calm, but is still swimming more than usual.
The only possibilities I thought up:
I read somewhere his water might need to be changed, so I've set up new water and will change it in the morning-giving it time to adjust to the temperature, and I put in the Complete Water Conditioner.
Could he just be chasing his own reflection?
Would putting in the Complete Water Conditioner now hurt him? it says it instantly makes water safe for bettas..
And, I'm just curious if he's expecting a female betta to make a visit.

Thanks for your help!

Answer
He's probably fine.  It sounds like he may be chasing his reflection. Is he "flared" when doing this?  If so, it's a good bet.  You can try putting something around the tank to take the reflection away and see if that puts a stop to it.  But make sure you use the mirror for at least 15-20 minutes a day just to keep your betta "excited" and not bored!! They enjoy putting on their show and it's fun to watch.

On the other hand, make sure you keep you eye out for any signs of illness (i.e. any white spots, white patches, red streaks, lethargy, not eating, etc.).  IF you see any of this, then there could be a problem.  Just make sure that you completely change out his water weekly if he's in an unfiltered tank.  Do research on Betta care if you need any help with this, as there is a multitude of sites dedicated to the care of these little guys!

Good luck!