Well, if you've never had a positive read on an OPK, that could be a concern. Are your cycles regular? For me, I had several cycles with no positive on the OPK (and no other signs of ovulation). I've gotten + in the last 2 months though, so my doctor believes that I had several anovulatory cycles in a row. No O, no chance of a baby!
My advice (totally non-professional!) is to see if you get a positive on the OPKs this month (maybe also consider checking your CM, even if you don't temp). If not, then go in to the doctor. I know it sucks to "track" things during your cycle (with temping, OPKs, checking your CM, etc), but if you are concerned about the short amount of time you have to try, you will improve your chances by being proactive!
Also consider what your expectations would be from the doctor's appointment. There are a few tests that can be done that aren't a big deal (general blood work, semen analysis, STD screening). If you start down the infertility testing road, some of those can be rather invasive and, as they like to say, cause "discomfort."
How many months do you have right now to try before DH is gone again?
