Boy Fits - Mama Breakdowns

I am drained - completely totally emotionally drained. My son started throwing these massive screaming fits for absolutely no reason this week. We've had one every morning and evening since about Saturday. Oh my God - I am completely and totally wiped out emotionally by the time he's through. The worst part I think is that they make no sense at all. Something sets him off, something small that doesn't go right, or something we've told him to do that he doesn't want to, anything really. I think he's having a hard time realizing that the world does not revolve around him, and he must conform to our rules. He doesn't like following directions and doing something that's not exactly his idea and way. I think initially that's what starts his fits, but then they just get out of control. He gets so wrapped up in screaming and crying that he won't stop and listen and realize that what's going on. For example - yesterday morning he was screaming over and over at the top of his lungs that his head hurt. I tried to tell him that I had Tylenol for him, but he wouldn't stop screaming long enough to hear me. The same thing happened twice tonight. First in the bathtub he was screaming at Daddy that he could wash himself (over and over again), and he wouldn't stop, look, and listen long enough to realize that Dad was trying to give him the washcloth so he COULD do it himself. Then he was standing in the tub screaming (over and over) that he was freezing. But yet he wouldn't step out of the tub to be wrapped up in the towel Daddy was holding and pj's I had that would warm him up. My God the screaming is killing me. I have to scream for him to stop just to be heard over him. I keep picturing the hysterical lady you see in the movies who won't stop screaming and someone ends up slapping her in the face with "snap out of it!". I swear, I just want to smack him upside the head! But of course I would never slap my child. However, spanking on the other hand... well... he has gotten a couple of smacks on the butt. I finally got him calmed down again and tucked in bed this evening. Once we were all settled and calm again I asked him where these fits were coming from. They're new. Is there something going on that I don't know about? Something that's triggering them? He said he didn't know. He couldn't remember. Umm... okay. Then we talked quietly for a few minutes. I reminded him of what a big boy he is and how very smart he is. He's too big and too smart to be throwing tantrums like this. If he's upset he needs to use his words to express himself. He said he'd try. Of course he's six. There's no telling what will happen tomorrow. We could have a wonderful day or it could be WW3 again - who knows. Ugh, motherhood's a bitch sometimes. But he's the love of my life and I wouldn't trade a day with him for all the treasures in the world. He's six - I just need to keep reminding myself that he's six, and he'll outgrow this phase just like any other.