I must also add that although breast feeding holds back periods, it is still very possible to get pregnant!!!!
It seems odd to me that your cycle hasn't resumed its normal pace so to speak since it's been long enough since you stopped breastfeeding. It's very possible that this is simply a hormonal imbalance rather than going through menopause since you're only 39.
I'm having the same problem but I'm older than you are so it is probably due to some kind of perimenopause type of thing. I had a baby 16 months ago, had some periods then nothing for four months. I need to go to the doctor and get my situation straightened out which I will also advise you to do especially since you want another child. Best of luck!
I believe breastfeeding, however, suppresses menstruation at least for a while. For some mothers, there may be an absence of menstruation for weeks, months, and even years while still breastfeeding. as you know... after you stop breastfeeding, it's take time for your body and hormone go back to normal... so it's okay if you don't see real period at this time...
good luck
Have you taken a pregnancy test?