Harvard does not read an applicants file until it is complete. I would check the portal today (https://admweb.fas.harvard.edu/ha/Ap...cantFrame.html
) to see if they received the supplement and ACT scores, although the scores may take a few days to get there.
If the application fee is a lot for your family, you can apply for a waiver. See: Harvard College Admissions § Applying: Requirements
"If paying the application fee would cause a hardship for your family, please request a fee waiver. You or your guidance counselor may use one of the official forms or may simply write a short letter asking us to waive your fee."