I would say yes, happened to one of my as well but not from Pleco, WC WC & WC and added some salt (if you wise, I did with mine) it will back to normal in a few week. Good luck
Disk edge looks like there are signs of damage, already changed the water when i found out this morning and added melafix to replenish the stress coat. Can't help but be worried about the little girl. She's not eating right now may e because of the stress so I know she recovers soon