Work sucks!

Man, the past few weeks of work have really been trying my patience. My boss Carolyn, who has always been so sweet and giving, has become Mrs. Hyde or something. All of a sudden at work I can't do anything right. It's not as if it's that complicated either, we're just cleaning for crying out loud! but I'm either too slow or too fast, and I'll admit when I go too fast occasionally I'll miss something. But I feel like I've been receiving some overreactions on her part for weeks now, and today was almost the straw that broke the camels back.Today I wasn't supposed to work, I got the whole week off until tomorrow, as it's spring break and my little brother James was visiting. But I checked my messages around noon and my boss says I'm working. I had nothing to do today, and I thought I could at least make a little money, so I didn't tell her I wasn't on the schedule and just decided to go. I then get a call about the time she's going to pick me up( a little early actually). "Where are you! Why aren't you out here waiting!" I responded that I was waiting right outside my house. Then she chewed me out because she said I should have been waiting at the back side of the school- this is where I get picked up on school days after class by her. Only it's spring break, so why would I be at school? Anyway, I made the 20 minute walk over there because she couldn't drive over to pick me up due to the fact she was going to pick up another employee in that direction. Whatever, not really a big deal, but it bugged me. We were still on time to our appointment too, so it all turned out OK, or I thought it did. Anyway, I worked extra hard today to make sure I was quick( but not too quick) and didn't miss anything. I did a great job in fact. Then on the way home she keeps telling me I need to pay better attention to the messages she leaves because she explicitly told me that she was going to get me at the school...by the way, I checked the message again when I got home, and she didn't. I was pretty bothered, so I informed her that I wasn't even supposed to work today(she made the schedule and I wasn't even on it, so she should relax because I did her a favor working on my day off. right?). Then she asked me out of the blue if I had ADHD, because I "show almost all of the symptoms". I dunno, but I took this as a dig, and now I'm kinda upset. Not upset enough to quit, but oh so close. Now that I've vented, I'm better.