Why am i getting a positive ovulation test so late in my cycle?

I had postive ovulation tests on cd 13 and 14 and then slowly faded. The second line never went completely away but then today I tested, which is cd 18, just because Im addicted to testing and i got a another VERY positive test again. My cycle is typically 30 days and I am on my 5th round of femara. Could i be ovulating a second time? I have been also having a lot of cramping similar to ovulation pains but more towards the middle and its wierd twinges all over including my ovaries and uterus so I'm very confused. Could this just be a painful ovulation? or maybe a double one?