First, welcome to Tropical Fish Keeping forum.
I think what you are referring to is the fish's natural method of remaining suspended in the water. Fin movements maintain stability along with the swim bladder, otherwise the fish would sink or float or be upside down, etc. Characins (tetra) need to do this constantly.
However, there is another problem lurking, and that is stress. All tetra are shoaling fish, and must be in groups. They will be under stress if not, since they feel insecure and many species have various interactive behaviours within their shoal (group). Minimum 6, preferably more if space permits, for any tetra (some need more). Don't know the size of your tank, but there should be more of this species.
You can read more about this in our profiles, second tab from the left in the blue bar across the top. You can also click on the fish's name in posts when it is shaded to see that profile, example Red Eye Tetra.