There is a new guy at work who is very attractive. In fact, he is almost too handsome. He reminds me of one of my celebrity crushes.
Today, I was speaking to a group with him in it. Oddly, I found myself staring. After realizing I was staring (because he was watching me stare at him), I looked away. My face started to feel hot, and I knew I was turning red. So, rather than look at him, I would glance surreptitiously, trying with all my will power to keep myself from blushing; and then look away quickly--so as not to stare. I know--I'm special.
Later, I thought, "I am pretty sure he thinks I am mentally slow." Seriously, I couldn't talk, just stared or wouldn't look at him, and then I walked away awkwardly. He was just uncomfortably good-looking, and the rational part of my brain just found a place to hide.
Tiny Fey describes it really well. They did a few episodes about it.