Help !!!

Blanca
So I'm breastfeeding my 17 month old twins but I'm also trying to have our last baby. My cycle is 27- 28 days and my period is NEVER late . . well we have tried for 2 months & nothing 😕 . I do have a tiny cyst on one of my ovaries but other than that I'm totally healthy. Could something be wrong ?? When exactly is ovulation day ?