OCD?

So, ever had that day when your 'down-to-the-minute' schedule is thrown off by something tiny and insignificant? I have that happen to me all the time. I have everything planned and then something happens and suddenly, it's like my will to live is drained. I have a total inability to move past it and just recover the day as best I can. Instead, it's like I go into total lockdown and wait for the day to end so I can start fresh the next day. I look back and find that thirty years have gone by.
How do I stop this cycle? I can't seem to understand the cause of this process and most importantly I can't imagine how that would change anything.
Just Me!