Weird happenings with tamagotchi p1

So I was playing my p1 and i had tamatchi, took care of him the way I should have, but somehow I got Nyorotchi...? Isn't that a kutchitamatchi character? I opened it up to clean a few days ago and I took the little piece that holds the screen steady cause I forgot where it went, could that have something to do with it? I'm so confused; please help.

It is possible to get unhealthy characters from Tamatchi if you take bad care. How high was your discipline? Did you let the hearts empty out a lot? I've gotten Tarakotchi from Tamatchi before by taking bad care.

Discipline was 1 away from being full, and I only let it drop 2 hearts once or twice. I actually love Nyorotchi, I just have no idea what's going on.

Edit: I also just realized it kept some or all of its discipline

Unless there are glitched graphics, missing or faint pixels, or unusual noises coming from your Tamagotchi - basically obvious hardware malfunctions which would be clearly evident as soon as the device turns on - there is no reason to take it apart. If the Tamagotchi evolves at the usual times, then the physical device is good working condition. If you have misplaced part of your P1 in reassembly, check these photos for the correct placement.

If your tamagotchi slept in its messes, that could cause it to turn into a bad care character. I know of a similar story where a person took decent care of their tamagotchi but it made messes before it went to bed and thus turned into the worst character on the growth chart.

Thanks for the photos! Will take it back apart to fix as I didn't tighten the screws enough the first time . I did not let him sleep in his poop though.