Late period going through change

Hi I have pcos Polycystic ovary syndrome and had trouble to conceive, had my girl ivf when I had her they said I could conceive natural, I am now 42 wanted a brother or sis for my girl can’t afford ivf now but not had a period for 21 days I’m usually late as periods all over the place but never this long, I feel I’m going through the change but don’t know symptoms as took a pregnancy test the other day but negative, with this weather I’ve been hot a lot but nothing else it’s I’m thinking that this is it now no more children which breaks my heart, anybody any ideas please