Diet and irritability?

I feel like lately I've been really irritable and just generally angry at the world and people around me. I haven't been in a bad mood per say as I'm pretty happy with my life and the changes I'm making to my health and diet. I will admit I'm not the most empathetic person to begin with but to put it bluntly I feel like I've become a real b*tch since I started counting calories!

Sure plenty of the things I'm getting angry about are valid (shitty coworkers, etc) but they aren't things that bothered me as much just a month ago so I can't help but think there has to be some relation to my diet changes.

I don't usually get hangry and I don't feel like my anger coincides with being hungry, it's more just a general state of easily being angered and being more judgmental and irritable than usual. And no I'm not PMSing.

Is this normal? Has anyone else experienced extreme anger and irritability while starting calorie cutting? Any advice?