Fertility, Short/fluctuating Luteal Phase??

I'll try to keep this as short as possible, while providing enough details. I had to use Clomid to conceive my first 2 children; since then I have RE-read the book Taking Charge of Your Fertility. I have never had regular cycles, but From monitoring cervical fluid, I determined that my luteal phase is approx. 14-15 days (on clomid it was usually 16 days, but cervical fluid was much trickier to monitor). I had not been specifically tracking BBT (basal temp) due to being in the phase of not preventing but not specifically trying to conceive. After 2nd child was born I refused to go back on BC. Cycles initially were 37-40 days, but luteal phase consistent. Now that we are ready to really try, it seems things are way out of whack. Had a 42+ day cycle dec to january; Thought perhaps it was actually an annovulatory cycle (I know, had I been checking BBT, I would know for sure!) b/c about 2 weeks later I had tannish spotting for about 3 days that I thought was perhaps ovulatory spotting and was accompanied by sharp left lower quatdrant pain that I assumed was ovulation (have had occasionally in the past and it matched up with a period starting 2 weeks later, ie 14 day luteal phase). Started checking temp more regularly by about day 10--it was low and then last weekend went up .4 degrees. I assumed a thermal shift and that I hadn't ovulated during the spotting but rather the day before the thermal shift (miniscule amount of egg-white cervical fluid seemed to match); temp stayed up roughly 6 days and well, now only a week later my temp has been back down for the past 2 mornings, but no sign of my period (in the past, I've had a tri-phasic pattern with both pregnancies; when not pregnant, period starts within 24-36 hours of that temperature drop). What gives??? Partly a rhetorical question in that why, now that we really want to conceive, does the body go haywire and cycles getting progressively longer?? but it was almost like clockwork before (in terms of luteal phase). I really do not want to go back on clomid (took about 8 months first pregnancy, 16 months second, WITH clomid!)--I feel like when my cervical fluid "cooperates" (that fluctuates too!!) I can really tell what would be the fertile days, it's that obvious. So, this got longer than I thought, but what would be affecting a luteal phase that had been so consistent before. I have not been sick; sleep has been pretty much the same (been up a bit later at night for the Olympics, but not much), no new stress in my life.... and why such fluctuation in cervical fluid while we're at the questions! I will pull out TCOYF again, but sometimes I can't quite find what I want in there. I did a brief google search, looks like maybe extra B6 would help? But shouldn't there be plenty of that in the prenatal vitamins I'm taking?? Thanks ladies--I know there are many TCOYF fans out there from previous posts, so I'm hoping you can help guide me here! FOLLOW UP: First 2 posts already assume I am obsessing. I suppose from my question it may appear that's the case, but I really am not. Having long cycles means I only ovulate 8-9 times a year, so I have to be ovservant to maximize potential.