Chances of pregnancy with positive OPK

So my husband and I have a 3 yr old and 17mth old. We would like another baby and was hoping to conceive in the next few months so we can have the baby in the summer since I will be off work (teacher) and my son will be in school in September so timing would be perfect. We ended up having sex last night and I had a positive OPK this morning. I would rather not get pregnant at this very moment but if we did we would happy just sooner than hoped for. My question... how likely is it that I will be pregnant getting a positive OPK this morn? Thanks all🤗