Student financial aid question (pell grants, unsub/sub loans)?

My parents jointly made less than $100k last year, I was unemployed, and my mother is displaced (lost her job due to it being eliminated) before I submitted my FAFSA for my freshman year of college, but I received less than what I need for school in UNSUBSIDIZED loans. Is there any particular reason for this? Should I file for special cirstance? Thanks.