I started TTC when I was 36 and 2 months. Got my BFP 10 months later. I missed a couple of cycles trying due to my OH being away with work - so in all I think it took 8 months. I think the average is a year. I had started tests etc and was starting to worry. I had acupuncture as I am a trained acupuncturist and really felt this helped to regulate my cycle.
As for symptoms I genuinely couldn't tell the difference between pmt and pregnancy.
Would defo recommend charting a few months and taking opks. Make sure you really know your cycle so that timing every month is spot on.
Good luck ladies
and don't forget to send your OH for sperm tests. It's not always us!