Like a hammer in the back of the head

So I was outside working in my shop last night, painting the last of my trim (most of the trim in my house is stained but we decided for a brighter look in the basement and went with paint). As I was brushing with long strokes to keep it all even and thinking of some short stories that I had started but was having a hard time keeping going. I think the ideas were too big for a short story. It helps that I could incorporate several of them into one longer narrative. This actually got me excited that I might be thinking of another book idea (I am a little mad that it is only months away from NaNo at this point, because I am still doing the dark romance for my NaNo project) I am wondering if I can hash out a first draft of this idea before November starts and if I will be burned out by then.

Am I the only one having a hard time keeping a short narrative in my head?