Jena.....first and foremost i was having trouble getting pg. having had been pg before i was completely ignorant to sec IF, so i was 2 years into TTC my ds before i even discussed it with my OB. the main symptom was my LP was very borderline in terms of length. then i had, low running temps, lots of spotting (for days) both before and after AF, VERY sore bb's pre AF, and 2 pos HPT's (on 2 separate occassions) only to have a temp plummet and extra heavy bleeding (at approx 19 dpo) inidcating a problem maintaining a pg.
although my cd 3 b/w came back normal, that really has nothing to do with the horomones (mainly progesterone) needed in properly preparing the lining for implantation and pg. dh's SA also came back normal, so we knew it wasn't him.
the only way to really determine LPD for certain is thru an endometrial biopsy. you have to go in on a certain cd (and i truthfully can't remember which day it was) but it 's during your LP, after O has already been confirmed. i actually had to refrain from TTC that month just in the event conception did occur, it would've been too early (before AF was due) to determine. there should be no possibility of pg because the procedure entails taking a tissue sample from the uterine lining, to determine if it's where it should be at that point in your cycle. mine came back "out of phase" indicating that the lining wasn't preparing properly for implantation. the hormones were not what they should've been at that point in my cycle. the first and most obvious course of action (for me) was to try and supplement progesterone. i even convinced my OB to give me the progest before i had my HSG. i KNEW i didn't need that test b/c i was certain i had conceived a few times over the years and i wasn't maintaining it. we had also already established that i had no O issues.
for me it was probably an "age" thing. at the point that i finally conceived my ds i was considered to be of "advanced maternal age" at the ripe old age of 38. as a matter of fact, normally IF testing is done in a certian order to rule things out one by one. my tests were all done out of order according to whatever cd i was closest to. my OB didn't even want me to waste 3-4 more months on testing so we just started whatever could be squeezed in asap.
before i tried the progesterone i had already added to my regimen vitamin B-6 (ER), one 81 mg baby aspirin a day , robitussin, green tea........and and anything else that was "known" to be good for fertility. B-6 and the baby aspirin are supposed to be very helpful in preparing the lining. and seeing as tho i was suspecting that problem, i thought i'd throw that in there.
anyway...all of my instincts were correct. i conceived the first month i used the progesterone. my only regret was not looking into it sooner.
if you do in fact have a LPD issue, it's one of the "easier" things to correct. so if you do get AF within the next few days (according to the cycle length that you mentioned ealrier) i would absolutely pursue testing for that with your OB.
good luck, and let us know how it goes!