Emergency fish help!!!!!! (Please don't judge, this is my first time having fish and I'm a minor)

[u/MainScarcity3514]

My tank has been cycling for over 2 weeks and everything has looked good, the pH is maybe a tiny tiny bit high (little above 7.0) but everything else is perfect. I've had plants and driftwood since week one and got fish today. I acclimatized the fish in the tank for 30 minutes before using a net and getting them in the tank.

The corys are perfectly fine and normal, but the tetras are not!!! Since I put them in, they started exhibiting really weird behavior, they would swim around frantically and then go limp and not move for about 5 seconds. I turned off the lights and assumed it was stress. It's been about an hour and I just went to check on them and they are laying fully down on the substrate not moving. I can't tell if they are breathing. Did I just kill all of my tetras?!? My water temp is about 75 and everything else is normal what is happening!!!?