Are these parasites?

She has acted funny since I got her, she doesn't refuse food but she'll chew on it and then spit it out she hasn't really eaten anything about a week or two. I took her out and put her in her own tank turn the heat up put some salt in there and added prazi pro. She continues to go after the food but doesn't quite eat it, almost like she doesn't know what she's doing. Looking at her up close today I saw this around and, is this something to be concerned about what it be part of my problem?

They don't move, I can't see any eyes, and they don't look like that picture. When I put live of black worms in there she tries to eat them and even did eat some this morning however she just takes forever to eat the worms. She's not a very aggressive eater and doesn't take in very much food is acting kind of strange almost as if she doesn't know what. She was curling her back disc almost straight up for a little while then I turn the heat up added salt medication now not so much anymore. She is extremely thin and I'm running out of options I don't know what

I'm not sure of wild caught or bit...the guy told me it came from rich Ross at stingray biology. However, I don't think I believe him. Water is at about 84, she may be stressed yet from being in the other tank with a couple larger rays. She ate a few live black worms this morning, she will nibble in shrimp but doesn't really eat a whole lot. I was told she's a BD/pearl so I assumed it was captive bred. I'm not sure what I should do? Keep salt or just keep water changes frequent?