Hey Darwin.
Welcome to Infopath.
I would create a new form and do soem playing and testing to gain familiarity before updating your production form.
It is a database type form? It has a query fields and data fields in the main data source?
If so I would make sure there are not multiple views and somehow it is opening with a blank view.
I recommend creating a data dump view, one with all of the data source fields on it, and then buttons to go to that view and back. that gives you a way to monitor what is happening with your data while the form is active.