No peak ovulation

Tara

Let me preface this with I usually ovulate between day 12-15. I'm on day 18 and still haven't had a peak. Did I miss it (as in testing every morning but hormones were going down when I tested)? Should I continue to test or save them for next month? Doctor tested me 2 cycles ago and said that my 36 year old ovaries are acting like a 30 year old so..... is it normal?