I am pretty sure that a temp spike when measuring BBTs indicates that you have already ovulated. So by the time your temp rises, it may be close to too late. The OPKs will indicate when your LH surges, and that happens 12-24 hours before ovulation. I have a tough time with OPKs, and found that I had to use them 2x a day to actually catch my surge. Good luck!
Common misconception... U ovulate 14 days BEFORE ur period is due not 14 days after it starts.... If u have a regular 28 day cycle then it is actually 14 days after the first day but if its longer or shorter then it will be a different day. I would suggest tracking ur temperature, when ur temp spikes u will ovulate 24-48 hours after that. I would say figure out when 14 days before ur period is due is and start testing 3-5 days before that with ovlation tests, u can buy them cheap off ebay and they work ok, they are pretty sensitive too. Then u shouldnt miss ur ovulation. Not all people ovulate 14 days before though so i would start testing early.
Good luck to you and remember that it can take a healthy couple up to a year to conceive so don't worry if it doesn't happen straight away for you.