Am I being a bitch?

Lately my friends have really been upsetting me. I don't know if I'm overreacting or not. Please someone take the time to read this and let me know.

First off my friend elise and I were going to work on a project for our 3rd period. But I didnt go to that class because I was busy helping out in a club that I am in. She texts me where are you, leaving me to do all the work. Then I text her and compromise on what we would each do. So I then tell her to send me a copy of her work, and she tells me why, if she could just send it to the teacher. I just said ok. Then I confront her in front of my other friends and told her I was feeling attacked and another friend stepped in and said that I just have to learn how to take criticism. I didnt want to argue with her and just agreed. Furthermore, the same friend elise and another girl that I usually sit with were sitting inside of the cafeteria, however neither thought to let me know. It was really cold outside that day and I was waiting and waiting for them outside on a table until I gave up since they would not answer my messages. I walk in and see them sitting there eating. I keep walking straight pretending not to see them and go and sit with my other friends. I told my friend Marisa and she told me that I was overreacting. I confronted her about it and told her that it had upset me that they hadn't bothered to even text me to let me know. She stayed quiet then said that she didnt know if I was going to sit with them or not. I usually alternate every week. One week I go with them, the other week I go with my other friend crystal. I just let it go. My friend crystal had called our friend alex a bitch because she didn't let us know that she wasn't going to sit with us in lunch. She wasn't kidding around she was legitimately mad. Then the next day was the senior walk and I find out that they went together. What upset me is that that same day I had asked her if she could give me a ride and she said that she was going to ask me for one. So we stopped talking about it. she didn't text me and ask if I was going to go, and I thought it was because she knew I wouldn't be able to give her a ride since I had asked her for one. Mind you I didnt want to go anymore because my grandmother had to go to the hospital because she got sick, so I dont know if that worry caused me to overreact? What also upset me was that she called her a bitch yet she hangs out with her and everything which leads me to think what shit she says behind my back and then acts like everything is fine.

Please let me know if I'm overreacting.