Daughter struggling after puberty started

She used to be a sweet, shy girl with lots of friends—now she’s pulling away from everyone and screaming that she hates us when things get too much.

Our daughter is 12, and up until recently, everything seemed pretty normal. She hit all her early milestones on time, talked early, played well with others, had friends in elementary school, and never showed any signs that raised red flags. She’s always been quiet and sensitive, but also strong-willed. We’ve done parenting courses and have worked hard to help all our kids manage their emotions—and while her siblings seem to handle things in a typical way, she’s always had these intense meltdowns that go from 0 to 100 in seconds.

The biggest changes started around age 11, right when puberty hit. Since then, it’s like a switch flipped. She’s withdrawn socially, has a really hard time making eye contact, and gets anxious in crowds or unfamiliar settings. She’s become much more irritable, and the meltdowns have gotten more extreme—full-on screaming, slamming doors, and saying awful things to us in the heat of the moment. Later, she’ll feel bad and sometimes cry, but it doesn’t stop it from happening again.

She struggles to talk to anyone outside of the family unless she knows them well. Even with people she does know, she can seem a little “off” in how she interacts—like she’s not quite in sync. She doesn’t jump into group activities like other kids her age, and making new friends has become really hard for her. The few friends she had have drifted away, mostly because she pulls back and can’t seem to just “go with the flow” like other kids do.

School says she’s doing fine academically and that she’s polite and sweet, but they’ve also noticed she has a hard time seeing her own part in conflicts, and they’ve mentioned some social challenges. Her doctor, after talking with us and seeing how things are going, is now recommending we move forward with a referral for further evaluation.

The thing is, she also has so many amazing qualities. She’s funny, empathetic, deeply caring, and really smart. She picks up on sarcasm and jokes, and she’s able to understand more abstract or subtle conversations, so it’s not like she’s completely disconnected. But something just seems different. And it’s getting harder to pretend that she’ll just "grow out of it."

I’m wondering if anyone else here has gone through something similar with a child around this age? How long did the process take from referral to answers? What were the signs in your case, and did you feel like you were taken seriously early on?