Tears dry on their own

There's a TV series on Universal called Being Erica. It's about a woman who travels through time to remedy what she's done wrong in her past. I would fuse it with 24, resulting in Being 24. That would be a perfect caption for my self-centred reflections on the world. (I won't recollect my medical problems this time, just a short note here: finally I've ordered the magical pillow for my backache.)
Okay, so the main topic. It's my moodiness again. There's a scene in Crash when Sandra Bullock is coming down the stairs talking on the phone, and she says "I am angry all the time, and I don't know why." (You can watch it here.) This scene comes to my mind every now and then, and I've just been in this same mood recently. Of course you can blame it on the conditions, you can blame it on anything from menstruation to public transport, to national politics; nevertheless, the problem is all the more frustrating. Sometimes I get so annoyed that I start yelling at whoever happens to be next to me, and it even gets worse if he tries to calm me. Sometimes I even want to cry, but I never want to show this to those around me. I start turning my head this way and that, and I also have to take deep breaths to suppress the tears. I try it so hard that suddenly I realize that I'm actually laughing. Of course I don't want to show it, either. For one, it would be impolite to laugh in a conflict situation, secondly, I don't want them to think that my anger wasn't serious. So then I try to stop laughing as well, but I cannot, so finally I realize that I'm not angry any more. That's how it goes. But is this a solution? I don't think so.
I came to the bit too selfish conclusion that maybe I spend to much time with my sister and my boyfriend, and maybe that's why I'm too angry at them. So I've made the Gilbertian decision that maybe I should spend more time alone, maybe also indulging myself, but that's not the real point. Just let me be alone and work things out in my own room, at my own pace.