short luteal phase

Lilamathews
for the past 5 months I've had brown spotting 3-4 days before my period. in April I got pregnant and had a early mc at 5.5 weeks. I couldn't help but wonder if I had low progesterone. called the dr and she said skip trying this month come in for blood tests 9 days after ovulation and a endometrial biopsy 12-13 days after ovulation. does anyone think this is crazy aggressive?? I've only been TTC since Jan and got pregnant in April with the mc. I kinda want to just ignore it and keep trying until the magical year mark when infertility is an issue. I should also mention I got pregnant in one cycle with my now 18 month old son