I created a form with 2 text fields, name and email address. When I placed the short code in the footer it displays the default fields (name, email, subject, message) instead of the form I created.
Not sure if it happens in all themes or just the one I'm using.
This is the theme I'm using.
http://themeforest.net/item/care-medical-and-health-blogging-wordpress-theme/868243