Blood testing... when? (kaiser Permanente in California)

I am supposed to get af tomorrow (hopefully not) but I’ve been testing with BFN (I usually spot the night before and nothing!) I’m currently 15/16 DPO — I have SOME symptoms (trying not to symptom spot)

Basically I was wondering when I can get a blood test done. When will kaiser allow you to get it down. How many days past period? (I tried to look it up but can’t find anything..) if you know please let me know!