I hate to go with the obvious.. but I feel like it COULD POSSIBLY be about her texting or talking to her boyfriend, or a guy that she is interested in, at night then he starts to end the conversation and says he's "goin' to bed" but she wants to keep talking to him. She lets him go and goes about her business till her mind takes over. She's thinking, "Now what the hell is that boy/man up to??", from the most innocent things as in getting into trouble with his friends, or the worst which is him with another woman. She doesn't want to think of such things but her brain just won't switch off. I know the feeling.
I hate to go with the obvious.. but I feel like it COULD POSSIBLY be about her texting or talking to her boyfriend, or a guy that she is interested in, at night then he starts to end the conversation and says he's "goin' to bed" but she wants to keep talking to him. She lets him go and goes about her business till her mind takes over. She's thinking, "Now what the hell is that boy/man up to??", from the most innocent things as in getting into trouble with his friends, or the worst which is him with another woman. She doesn't want to think of such things but her brain just won't switch off. I know the feeling.