How to determine Breastfeeding is not going to work

Mu Baby is 7 weeks today. When she was 1st born my Colostrum was even coming out. Idk why! I had to put her on formula in the Hospital. I have tried pumping..NOTHING but Drops come out, my nipple sooo Sensitive & sore, Crack & Bleed. I've tried a few different pumps, Hospital pump, Haakaa (Silicone pump), etc....

I have tried Nursing, she latches very well but doesn't stay on long due ro crying from what I'm guessing is she Not getting anything.

I've been doing

-Fenugreek EVERYDAY

-Lactation Cookies

-MotherMilk Tea, I asked for a Prescription from my Dr & Did Teglan for 2 days.. My stomach was so Torn into pieces, running to the bathroom between Diarrhea & bout to Vomit.

I want to Order a Liquid to bring my supply up. I feel like i have milk but nothing coming out.. unless I have it but just not enough.

I want t ok Breastfeed her Badly.. This is the 5th Formula we have tried her on due to her Vomiting. I know the best thing for her is my Braestmilk

I hear Mothers say it but

At what point, does a Mother say... breastfeeding doesn't work ???

Or, how do I know???

My heart is Broken & I am Devastated about this.