I've never been even-tempered, but over time my anger has become harder to control, and little things can spark it off. If I'm having trouble with a video game, for example, I start swearing and punching myself in the thigh (I never used to swear at all). I've even been tempted to throw my 3DS across the room a few times.
Yesterday I wasn't feeling well, and I got snarly at my brother just because he asked me to do something. I stayed that way for a while, and even when he gave up talking to me, I found a "reason" to be angry about that. This is far from the first time that has happened.
People, inanimate objects, and animals can all spark the rage without warning. I rarely lash out at anyone or anything, but I have lashed out. This bothers me, because I don't like hurting people, and I never used to be this way.
It's not consistent either. Sometimes things that would have made me angry hours earlier don't bother me at all, and other times I go from perfectly happy to raging because of one word.
I've found a few methods of calming myself, but I never remember them when I need them. Even while I'm angry, I sometimes know that I'm being irrational, but it doesn't stop me, and most of the time I feel justified in my anger.

Does anyone have any advice? This is leaking into every part of my life, and I'm worried that I'm going to hurt someone, either physically or with words.