Opk somewhat Confused! EPO & Clomid

Gladis
So i just finished my 3rd round of Clomid and i started testing ovulation I bought these online but i dont know if these work , shouldn't they have a second line no matter what?? I dont see any on 3 top ones ?? I am also taking epo so i dont know how that effects my clomid?? I need answers please has any one taken epo and clomid and what effects did the combo have