Shadowbox JS and Media Library

I’m trying to create two galleries of pics with Shadowbox JS but once I publish the first galley (via “insert media”) with the first set of images and I upload the second set, I cannot keep the two galleries separate from each other, they all bunch up in a larger gallery since they are all pulled from the media library.

Is there a plugin to separate in sections the media library I looked but no luck.
Thanks!

PS I just tried to create a second gallery via “insert image” and selecting a few but they all ended again with the other images in the gallery with previous images..arghh