Low progesterone?

I am on cycle 7 ttc.  Had a chemical pregnancy during cycle 1 but otherwise all BFNs. 
I started charting right away and what I have noticed is that I ovulate around CD 14/15 and start spoting around CD 22 and AF typically comes around CD 28.  At first I thought the spotting was a good sign (possible implantation spotting) but now I realize it's not implantation spotting and I'm afraid this means that implantation is unlikely if I'm already spotting around the time implantation should occur. Especially since it happens every month. 
Has anyone else had trouble with this?  Is there a way to increase progesterone and extend the leuthal phase? I'm assuming I'll have to speak with a dr. But as we all know they won't do anything until TTC for 1 year. It's so frustrating getting those BFNs every month!
Thanks for your advice ladies!