flash rage VS building pressure cooker

I experience the latter much more often. It seems like "anger management" help I've gotten was geared towards the former and absolutely useless for the latter. I don't have any trouble recognizing when I'm starting to get angry. Most of the time it comes on slowly like a building swell. I'll run into something that triggers me or just start having negative thoughts for some reason. At first it's just an intense feeling of anxiety, but then I find that I can't make myself think about anything else. I just start feeling distant and glazed over. I get really flat externally and have extreme anhedonia and anxiety/depression/rage building in me. If someone around me tries to distract me or asks me if I'm okay having to respond just makes it worse. It's like I don't want to distract myself and the notion that I should makes me not want to. I think I'm to intelligent for me own good because I can easily be doing something else that involves my brain and not feel sufficiently distracted. It can stay lurking there for hours or even up to a day or two. Boredom and down time is the absolute worst. Driving is really bad too. I drive very fast when nobody else is in the car. I think it's more anxiety converting into anger than plain old anger.