Forehead filler with natural volume and same-day procedure

Hello. I have been wearing a hat or covering my forehead with bangs because of my flat and dull hairline, but I am writing to inquire because I would like to take this opportunity to add volume with a filler procedure.

Since the forehead is a large area, I am concerned that it might become uneven or look artificial after the procedure. I would like to know how many cc of filler is typically needed to achieve a natural volume without being excessive. Additionally, I would like to know if swelling can descend and cause puffiness around the eyes, and if it is possible to return to daily activities immediately.

As a working professional, I would like to visit on the weekend for a personalized consultation with the director and receive the filler procedure on the same day. Could you please let me know if it is possible to book an appointment this Saturday afternoon and provide an approximate cost estimate? Thank you.