corydora panting

Hi all, New to this forum. I've had a betta for about two years and recently decided to expand into cories. My local tropical fish store is run by hobbyists and has high reviews, so I decided to trust them when I bought two pepper and one albino cory to accompany my betta in my 10 gallon tank...

I noticed a couple of days ago that my big female bronze cory was panting. Normally they move their mouth/gills when eating food, but she does this constantly now and has never shown this behavior before. Other than her mouth/gills moving rapidly, she also goes up for air a bit more than usual-...