Suggestions?

   I've noticed lately that I constantly have a to-do list running through my head. Being a person who plans, and generally is fine under pressure, I'm finding that I've just been uneffective with my time lately. To be real, I'm trying to figure out if this is because I'm trying to make excuses, if I'm just changing or if I'm struggling with being out of control. I have realized that I've been furious when I feel that someone has interfered with the time that I have budgeted out for myself. This is interesting because some big things have not bothered me (like someone coming 45 minutes late for an appointment and affecting a time I was supposed to have a surgery) but been livid when my husband makes a decision that adds a 20 minute delay or causes me to have to do other tasks later.
       Seriously, I'm looking for suggestions before I turn into a raging maniac. What are some strategies you use when you are unable to get things done? Overwhelmed? Frustrated? I think the real problem is that I'm struggling with the mental energy it takes to deal with certain people in my life. Once I get aggravated, my focus seems gone for the whole day.
     In other news, it's my last day of being 39.