Ovulation and sex

Ok I have a question. My hubby and I had sex on cd 11, 12, 13, 16, and 17. I had positive ovulation test on cd 17 and 18 but 18 looked a little darker. We were going to on cd 18 also but I ended up having to come to the children's hospital with our 2 year old to get her feeding tube. Is it still possible that we got pregnant or do y'all think we missed it? New to being ttc over here.