Ovulate without a period?

Cecilia • 29, married. Ttc number 1!!
I stopped birth control in dec and was getting regular periods. However suddenly I didn't get a period in April or May. Took several tests which came back negative. I'm thinking about getting an ovulation kit since now Glow is all messed up and I don't know when my fertile days are anymore. But should I wait to use the ovulation kit until I get my period again???