Big letdow

We've been trying to TTC baby 3 for 15 months now. Fertility doc found I have very low AMH but since iud out I've finally gotten relatively normal cycles usually every 24 days and I've never been late in my life since I was 12 even when I used to be like clockwork on the 28th day. So I was hoping for a miracle when I found myself 8 days late but bfn on hpt.. bit today AF came full force :(. Question, does this mean I'm starting to go into menopause I've already been told my AMH is very very low and I've never been late. Fertility doc is giving me little hope bit other 2 pregnancies easy. She's kinda bitchy anyway. But idk any other explanation for very late AF. Could this mean menopause is setting in in only 37??!!