Testing opk

Erica • Married with two beautiful boys. Trying to loose the weight and not get prego at this time.
Ok so I tested while I was beginning to ovulate. I had my normal ovulation signs beautiful clear thick stretchy mucous but the tests never gave a really strong dark line. Did I miss ovulation or is there a chance that we may have conceived and that's why I no longer have the mucous anymore? I normally have mucous for a full week. It was only two days. I have never tested positive even on pregnancy sticks till I was like 2 months along already. So can that also be an issue with OPK?