Low progesterone?

Anyone here have any experience with low progesterone, and any success conceiving with treatment? I think I may have low progesterone. I spot lightly bright red or pink for 3-5 days (this has only been happening for the last 4 months--before I'd have a bit of dark spotting for a day or two) before AF starts, and AF is super painful, heavy, and clotty. Been TTC for 6 months, and I'm 35, so I'm thinking of finding a specialist.

Any shared experiences would be appreciated.