Hi Jen,
Sometimes feelings of annoyance are valid even if we may think it's being petty or impatient. Grant yourself that much. You seem to be able to pinpoint where and how it's all coming up but you don't like that you're reacting to it the way you once use to. Were you giving yourself any outlets before when you were patient and even tempered? Just because you don't/didn't express the anger/annoyance doesn't mean that you didn't feel anger/annoyance. Maybe it's seeping out at the seams? I have anger issues myself and I'm doing a workbook on it. It's teaching me a lot about anger, where it comes from, the many ways it can be expressed and the different reasons why we feel the anger. Exercise is helping me too.
I think it may be helpful to express these feeling more consistently in your journal. Maybe then you can see where and why this is happening. Did you read the past entries leading up to this? Are there any tell tale signs in them?
Whatever it is that's making you a little more snappy. Stress from your job and world events no doubt are contributing to this.
I don't know if this helps. Me trying to help you with anger issues is like the blind trying to lead the blind.
((((((((((Jen))))))))))))