Am I the one whos to blame?

When i was a little girl, life was great. I had plenty of friends, and i was loved and adored my most everyone who met me.  I hardly remember any times that i was ever miserable, and I loved my mother so much, that i slept with her until i was 10 or so. i never really thought there was something wrong with my mom back in the day. she always tried to do her best. Sometimes i would wonder why she would be so paranoid about little things, but she was very protective of me growing up, and i never ever would think of my mom badly back then. but once i got into middle school, things started to change. My body was changing, I started to like boys, and on top of that, i started to have my own mindset, and realized how uneducated i was compared to other kids. I could barely pass my math class in 8th grade. I think that my mom had babied me so much, that she failed to teach me much of anything when i was younger. 

Today, i had a relatively boring day, basically sitting on my computer and organizing things. later me and my mom went to the store, because she needed a few things. What i don't understand is why i have to follow her no matter where she goes, and she will not let me go alone and get the things that i need from the store by myself. If i try to argue, or ask why, she yells at me in the middle of the store, which I think is ridiculous and embarrassing. I am 18 in four months, you'd think i should be able to walk around in a store by myself. so when she was finally done, and paying for her stuff, i told her that i would be in the face health section. she said okay, so i went and found the things that i wanted to get, and went back to pay for them. I saw my mom waiting for me on the other side, but she was looking for me in the wrong direction. I called out her name, but she wasn't seeming to hear me, and it was my turn to pay for things, so i payed for my things, and i was expecting my mom to be in the same spot, but she had vanished. i looked around and couldn't see her, so i figured she probably walked to the car to wait for me. so i walked out there, and she wasn't there, and i walked back, and there she was walking towards me. As soon as she saw me, she started yelling at me, asking why i would do that to her, and that she was looking around all over for me, but i was right in front of her, and even yelled out her name a few times. She called me a spoiled brat a few times, and told me i ruined her mood, and her enjoyable shopping trip. I said sorry, and she made me say that i would never wander off again. But i TOLD her where i was going, and she confirmed it with me, and she was not responding to my yelling when i was paying for things. 

Maybe i am just a spoiled brat. She is right. I get almost anything i want (things wise) and i am VERY blunt, which can be mistaken as rude and bitchy. 

i wasn't always blunt, But with my mom, and my family, i can be very blunt sometimes, and i can express my feelings, and not care about what anyone else thinks about them. My mom doesn't like that about me at all, and she always tells me she wishes for the "old, cute, sweet" Amber back.