Ovulation question

My DH have been TTC for almost 5 months now without success. My cycle still isn't completely normal since coming off BC last March. In the last 6 months my cycle has been anywhere from 22-30 days. I just started using OPK's in September. I had positives in both October & November, nothing in December. I'm now on CD18. Is it still possible for me to ovulate this month if my cycle is closer to 30 days again? This is getting so frustrating!!!! Any help would be much appreciated.