have a lot of questions

I had a miscariage June 2009.I am having trouble getting pregnant again. I have children so I know it is possible for me. I think I may have low progesterone. I know low p can keep you from sustaining a pregnancy past the first trimester. I am not sure if this is my problem though as I do see a temp rise after ovulation. can I take fertilaid after I become pregnant if I find out I am? I am in the waiting stage now. Also can I use natural progesterone cream or take prometrium while using fertilaid? What test do I need--- hcg? cycle day 21 test? progesterone blood test? I have been bbt since like 1998 but started using fertility friend in 2007 I think. I have 29 cycles charted on there, and of those 29, 13 of those are unovulatory.I started using the ov watch in march 2010, or Feb cant remember which anyways the watch and my fertility friend software dont always match up. one says I ovulated on one date the other says I ovulated on another date. It is very confusing! my luteal phase changes from month to month my chart shows  12, 11, no ovulation, 11, no ov, no ov, 12,no ov, 13, no ov, 12, no ov, -27, 13,23,no ov, 13, no ov, 85, no ov, 9,no ov,16, no ov, no ov, no ov, 6, 13, 5. the last one of 5 is the one I am on now so I dont know yet what the number will be.  what is going on? very confused! I know this is a lot, but I have a lot of questions!!! if I do have low progesterone, if I am pregnant now what can I do to prevent another miscariage, take fertilaid, use prometrium, use natural progesterone cream what? I dont want to wait till it's too late!!! also I didn't know where to post this. any help would be appreciated.thank  you