Short Luteal Phase

This month I started spotting at 9 dpo... For the last 5 cycles I have spotted at least 3 or more days before my period. I’ve always had issues with this, but my doctor says that my bloodwork and everything looks fine so she isn’t concerned. Years ago I took Vitex and it helped. I ended up conceiving my son while taking it. That was 3 years ago. A few months ago I tried Vitex again but it completely messed me up and I had a 45 day cycle so I refuse to go that route again. Does anyone have natural ways to lengthen their LP? Does anyone else have issues with spotting before period and has still conceived?

I’m 10 dpo and spotting is becoming heavier.. I just know af is on her way...