I don't know why I haven't conceived yet, after 7 months of trying. Could there be something wrong?

My boyfriend and I have been together for 1 and 1/2 years now. And we've been TTC. For about 7 months, and haven't conceived yet. We've tried all different positition and have tried to calculate my specific date of ovulation (my cycle is generally very long, 40-45 days) and I've had so many pregnancy symptoms the last couple of months, (pink mucus the last couple of days of ovulation, sore back, tender breasts). People tell me I may be having phantom pregnancies, has anyone else experienced these?