My Scatter-brained Self

Just to warn you - this may prove to a be a little too much information.
I admit, I am not always the most focused woman on the planet. I can go off-topic with the best of them, as is proved by the sheer number of "stream of consciousness" type entries I have posted here. For the most part, however, I can handle a number of tasks with some semblance of efficiency...except for one week out of the month...during which I become

unfocused, distracted, completely scatter-brained.
Yeah, this along with your typical cramps, moodiness...and I lost my train of thought.
Argh.
Is this normal? I haven't been able to focus on more than one thing at a time all week, and I've been lucky when I've managed that one thing. I think it may be getting worse.
Now, if you'll excuse me, one of my cats is tapping my leg with her paw. Apparently she wants something, and it's...distracting.
I'll post again when I can concentrate.