I figured out today that my caffeine headache wasn't just a headache. It was the beginning of a cold.
While I was able to focus/concentrate for the most part today, there were times that I felt like this.
It also makes sense why I haven't slept well the past few nights. Plus Hubs said I was tossing and turning as well as being a bed hog last night.
The plan for tonight is hot tea and early to bed.