What am I doing?!!! I'm in charge....right

Well a few months ago when Linnea was about 18 months old I thought the terrible twos had come early...boy was I wrong!!! Yesterday was one of the most, heartbreaking, frustrating, confusing motherhood days I have had. Linnea was acting like I remember acting as a headstrong, always right 16 year old who knew better than her parents and wanted nothing to do with them. She would as for something, like a piece of candy, I would say no not right now, maybe after lunch. Tears, screaming, and throwing herself down on the floor followed. So I stay calm and say, that is not the way we get things. She looks up at me and screams "No!!!!" Imagine your two year old shaking her finger at you with a teenage look on her face...it took me back a little bit. Yesterday every limit or every thing we told her to do such as safety things, or breaking rules, or treat and movie limits ended up with an emotional breakdown. Well we eventually decided to get out of the house as a family and go to the store together which Linnea generally loves to do, but we get to the store and she screamed because I put apples in the cart, or I didn't get the bananas fast enough...thank goodness Derek was there to help, he eventually just took her out to the car since it was all screams, not just crying, but disrespect (which I have an issue with at any age.) At this point I think both Derek and I were very confused at this new behavior and how to go about dealing with it. I feel that I should always explain at this point why we don't do things, calmly. So everytime she would yell at me, I would say "look at mom...you don't speak to me that way, we always speak nice." you know just simple things like that. I can hold her attention for a little while if I say to look at me so hopefully some things sink in. The real heartbreaker came later that night, she was screaming at Derek and he was trying to calm her down by holding her and she did the typical squirming and screaming to be let loose, well I walk in her room to help out and she looks at me and shakes her finger and yells, "No, Go!!!" Basically telling me to get out of her room two year old style....well that broke my heart, I actually went and cried a little. It was so hard for me since I have started my fieldwork and basically have a full time job so I don't see her that much during the day, so when I do have days with her I imagine us playing our games and having fun, and baking like we always do over breaks or days I am home, so to have my sweet girl tell me to leave was too much for me at that moment. So Derek put her in time out and with tears in my eyes that were noticeable I went out there and I said in my cracking voice, " You do not talk to me that way!!! Do you know your mommy loves you? That hurts me." Linnea's crying and screaming stopped the second she saw my red eyes and my tenderhearted girl came out again and she ran up and gave me the biggest hug and pat on the back. After that the night went pretty well. I could not believe though the attitude and the change of yesterday. She does have a stuffy nose, so she doesn't feel 100%, but that in my opinion no matter how old a child is does not mean you speak disrespectful to your parents or anyone. I need to be stronger and not let my kids see me break down like that, but yesterday took me completely off guard. I'm not afraid to let people see me cry, but I do realize that my kids will hurt me through life either with choices or stages they go through, but I hope that they never doubt they are loved and that we expect respect from them. Sorry to vent so much, today has been much better with not even a fraction of the screaming fits, she is pushing the limits, but at least she is listening to us when we tell her to stop a behavior. It is all part of life experiencing these different stages, I hope that we can instill the right principles of kindness in our kids by example and remaining calm and collected during freak outs :)