Irregular Periods - ovulating?

Hi! I've been technically TTC for 3 months now (we were not, not trying before this though). I get a period about every 6-7 weeks. I don't know when I ovulate (I get the symptoms for weeks). I tried buying those ovulation strips, but they say I'm ovulating often. Should I invest in the more expensive tests? Anyone else have these problems? Anyone have this problem and still conceive? We've been told to just have sex every other day until we get pregnant to be safe, but that's been hard for us to achieve. I'm getting frustrated and worried! I have obgyn appt in a few weeks, but I don't think she'll be concerned until we've been trying for a year.