Young Budgies Behaviour

Hi All, My two clutches of young had to be moved to cages while i cleaned and disinfected my avery, also had to seal holes up for a mice problem and am treating all my birds against infection from contaminated food. what i find strange is the young scratch all the food out into bottom tray, then eat it, roll in it and sleep on it. Never seen this behaviour in 3 years i;ve bred. Is this normal?

Also i placed a female away from her mate in Avery but she screeched daily so i put her back with him in cage again but she did the weirdest thing! she sat at the foodbowl and picked all seeds out and threw them on the floor. Almost like a maniac! what is this behaviour? i took her out again and put her back in avery and she still screeched and kept herself away from other budgies. now with the move into cages due to Avery clean up she is as quiet as a mouse. well actually normal. what is that kind of behaviour? stress? breeding condition? ceres is very dark!