Are there any foreseeable complications that might arise when writing a short story and then realizing that elements of it would work well in a novel? I think it's been done with Faulkner re: short story "Wash" and novel 'Absalom, Absalom!' I also saw it with a musician who wrote a book and incorporated his lyrics into the narrative. I'm in sort of a quandary because I'm obsessing about it. I would like to do both but a concern would be for readers to see similarities between the two and think, "My, how unoriginal..."
If you're adapting a short story into a novel, you're going to be adding so much extra material that, even if readers recognise the basics, no one would call it unoriginal.
I've done it - a promo short story was published in a widely-read anthology, and then a couple years later I expanded it into a full novel. I was really up front about doing it, so I think that eliminated the "wait, I've read some of this before" surprise for readers. Also, I don't think I re-used ANY of the actual words of the story, just the characters and premise and basic plot. The only challenge I ran into was that the short story was essentially the climactic few scenes of the novel, and after writing the characters for almost a full novel and developing their characterization I realized that the climax wouldn't work in the way I'd originally written it, so I changed it around. And then some readers of the short story were upset b/c they liked the short story version better. (you can see comments at https://www.goodreads.com/book/show/23488490-in-too-deep? if you're curious)
Which is true, of course, and I thank you for responding. My short story WIP and the novel WIP are two different things/two different plots, with the only overlap being interior monologue about long distance traveling. My concern was with the characters having similar ruminations. Eh, I'll figure it out.