Don't blame you for being frustrated. I'm sorry your mom is being so inconsiderate and changing her mind at the last minute. Does she do this to you often? You say "she's so messed up sometimes" so it sounds like this isn't the first time she has given you a reason to be upset with her. I'm glad you came to PC. It's the perfect place to vent if you need to or discuss things that concern you.
Gayle