Yes, you can. You can see thumbnails for up to the last four Story videos on the Story page (bottom), where they can be selected and deleted.
- Can I disable the background music on my Storyvideo in Lumia Storyteller?
- Can I select folders from where photos will be shown on Lumia Storyteller?
- Is it safe to use Lumia Beamer?
- Where and how in online can I view a shared Lumia Refocus photos?
- Can I download my shared cinemagraphs back to my Lumia phone?