When you're informed your baby is kind of acting like a brat

Yesterday I picked her up, the new gig is a little more flexible so I pick her up on Tues/Thurs, and got an update from her teacher. She's been teething like a fiend (over 6 coming in at once!) and I gave them a head's up on her cranky factor when I dropped her off. At pick up, her teacher started with a teething update but then I got more info. Turns out, she wasn't that great. She threw a major tantrum waking up all of her class, and I'm fairly certain she refused to allow them to go back to sleep, she pushes the little kids, big kids and teachers when they try to direct her in a way she doesn't want to go and firmly says "no" to any and all requests. Uhm, yikes.

I felt like a complete failure. My baby is acting like a brat and I really had no idea. I see her when I come home where we make dinner, she demands to be held so I get to have more guilt that I can't hold her and chop up stuff with a very sharp knife at the same time so she has a mini-meltdown. Often she quickly contents herself with her pans or books so it didn't seem like it was all that unusual to me.  We eat dinner, snuggle with books and/or get a bath with a little playtime then bed occasionally she acts out and gets deposited in her crib where she cries briefly but then plays with her animals until her "time out" is up. Even on the weekends it's just a longer version of this schedule and then back to the lather rinse repeat schedule of our weekday life. Previous reports she was great and everyone loved her, now I'm worried she's become "that kid" overnight (or while I was at work and then at home not paying attention to less than charming behavior).

I know I'm overreacting, I know she's fantastic and everyone still loves her, I know she's incredibly independent and has no desire to do anything that isn't exactly what she wants to do which is fantastic for avoiding peer pressure but not so great for getting her diaper changed and I know she can throw herself down on the ground and have a major meltdown and that ALL kids do it. But right now, I also know that I feel like I'm failing her. My time away is leaving her to be raised by strangers where they are teaching her everything and they know all of her little quirks. Where I get updates on what she likes, what her accomplishments are, who her friends are, people know her name and I have no idea who they are. It's frustrating.

There are no good answers since the socialization is good for her. She's fantastic in new situations, we can usually take her anywhere without freak outs, we are good parents and everything really be ok. Today, just isn't a good day.