Ladies can I solve this?

So my girlfriend absolutely drives me nuts sometimes. There are two things she does that just get under my skin. First she text messages people like there is no tomorrow. We could be out together and she will start texting and unconsciously give me the cold shoulder. When she is in the middle of a conversation, she is almost captivated by it. Second she will make plans and at the last minute she will go, "oh I forgot I have this to do can you come over tomorrow?" Now I know she is still into me so thats not the reason. When I tell her about these she makes it sound like its no big deal even after I planned my day around it. Do any of you women have these traits? How should I approach this? Am I reacting too much? Any suggestions.