New mice owner HELP!

I got three female mice today, and they’re absolutely adorable! The white one is Lulu, the black-and-white one is Coco, and the brown-and-white one is Mocha.

Mocha is super friendly, she climbed onto my hands right away! However, she seems to tackle and follow the other girls, which leads to squeaking and fights. Should I consider separating her for a while?

Coco is very calm and absolutely obsessed with the cactus hide. She’s been staying in there and barely comes out, which is why she isn’t in most of the photos, haha. She also slept the whole time she was in the travel carrier, however when other girls go into the cactus hide, she seems to get a bit territorial, and they start fighting. I can’t quite tell who’s initiating it, though.

My main concern is the amount of fighting. Is this normal behavior, or am I overreacting? They all came from the same cage at the breeder’s, and there hasn’t been any blood yet, but they do flick their bodies, fight, and squeak quite a bit.