I have been arrested by immigration enforcment in the UK for working with fraudulent documents.
I am from a Balkan country and wanted to know whether this would mean that I also have a Schengen entry ban.
I cannot answer with any certainty whether you have a Schengen ban. However, it does seem quite clear that any such ban could not be issued by the United Kingdom. See the europa.eu page on the Schengen Information System:
The United Kingdom operates the SIS but, as it has chosen not to join the Schengen area, the UK cannot issue or access Schengen-wide alerts for refusing entry or stay into the Schengen area.