What's the chances false positives

Gabriela
Of taking three tests and having false positives or evap lines on all three? 
I miscarried on August 25th they tested my levels at 15 the day my angel baby left me, took a preg test this past Sunday: bfn. Took three today and yesterday combined and faint faint positives. Evap? False? Opinions needed. Don't wanna see a doctor yet that's a lot of money on a whim of what might be. 
Also, the app says I'm 3-4 days late on af.