Earliest positive pregnancy test??

Co

I am currently 6 DPO (we did letrozole, menopur, trigger shot and <a href="https://glowing.com/glow-fertility-program">IUI</a>). I am testing out my trigger which I now took 8 days ago and am still getting a faint positive. I am expecting it to be negative by either tomorrow or Friday and will continue testing daily after that. When was the earliest you got a positive pregnancy test??