I am graduating with my MSW this Aug, and starting my PhD program in Social Work three days later. From my understanding, regardless of the program you apply to in any field, if your research interests are not a match to the school they will not consider you since they have to consider funding etc. So research the schools and the faculty members and find those faculty member who you believe would be interested in picking you up as a student. Reach out and connect with the Director of the program. I know my relationship with the Director helped push my application through.
Considering that applying to PhD programs is arduous and overwhelming, I think this feeling of "imposter syndrome" can resonate among most of us who have applied to the programs, so you are definitely not alone. I would encourage that you try your best to strengthen your applications with higher GRE scores. Try your best and if you don't make it through this cycle, you can always apply again next cycle. Your worth is not determined by whether you get accepted or denied into these programs
Good luck