Fin clamping and breathing rapidly..?

Hi, so I got my first lot of fish.
8 rummy nose tetra
All is well apart from this one female. She seems to just stop a lot while the rest school around.

It looks like her fins are clamped up and she breathes heavily.

Any ideas?

The fish will paddle from side to side. Fish with shimmies may have fins attached to the air and have difficulty breathing. It can also cause the body to move or vibrate. To know more about the disease plz visit the link https://livebearer.blogspot.com/p/diseases-and-treatments.html

Rummy noses need a lot of plant to make them happy, they don't like open spaces.