Its not like she went to a 'surprise symphony'. She knew she would be there, if she is over 12 years old, she realized phones weren't allowed, so she should have called before she went in. Even if it was early, before their bedtime.
Your texting wasn't a backstep, I don't think. You weren't defending yourself, didn't R talk, just sticking up for the girls. I wouldn't bring it up today. No need to apologize.
