Fertility tests are normal?!

Me and my partner have been ttc baby 3 for about 15 months and I don’t think I’m ovulating regularly as my periods are so irregular (currently cycle day 57) so I had a blood test done to check for anything and it has come back normal? How is it normal when my cycles are a irregular and I do my bbt and ovulation tests every month which shows to me that I’m not ovulating all the time! I’m at a loss now on what to do! What do I do now?