@Xeek That's great news! :) I really hope he's okay. No, I didn't acclimate him, I'm still fairly new to betta (started last fall) and didn't realize that water from different places can have an effect like that.
@DragonFish I don't know the pH of my water at home. I brought him home over the summer and he didn't have any problems. The trip is about an hour and a half but I had the container wrapped in a blanked in a box. The conditioner is called "Splendid Betta Complete Water Conditioner." No soaps or anything got in the tank, but my fingers did smudge the side of the tank while I was resetting up the tank after arriving home - could that have caused something? That's why I suggested scrubbing.
The water is stable now and has been over the day (staying at about 76 F), but when I first got home it was kind of all over the place because I was trying a new heater and eventually settled on the heating pad (I don't use one at school).
Again, it was my mistake. I did not acclimate him to the new water - I didn't know something like pH had such a big effect and he was fine over the summer. Do you think he will be okay?
Also, I thought it was weird, but he was acting normal the first day I brought him home. But I've heard of bettas repressing stress.