Is there a way to create a package from a direct deployment?

Hi all, we're looking for the best way to maintain a large deployment between environments. 

We have the package created in our DEV environment but we don't want to keep deploying this into SIT every time we fix an issue, as it's a large package and some issues may be in progress and not ready for deployment.

I think ideally we want to create a package we can maintain in SIT as we deploy fixes to keep all the objects we've changed consolidated for when we deploy to UAT. Is there any way to create a package from a direct deployment or do I just need to manually create a new package in SIT and manually add all of the objects?

Thanks!