she has just given birth and is walking off the pain
yes is normal behaviour for a while
she will settle and go back to normal
did you get to see her laying eggs
they grip weed etc with front legs and tail and use the back legs to stick the eggs onto the weed
quite a delicate operation for something that can appear gormless most of the time
back on subject josh
there are many herpers overseas who use that substrate and any fine sand has the potential to cause problems from ingestion and inhalation
i and a few others use astro turf for easy maintenance
predatory fish can be funny sometimes, they will sometimes leave fish alone that have grown in the tank with them but eat new introductions,
i have learnt not to trust big mouthed fish
she was already sick and though signs were gone she may have still had it and the change of tank and water conditions brought it all back with a rush
would possibly have been better to do a waterchange on that tank rather than move everything into different tanks and water