still have no idea when I am ovulating?

When I post on these apps I usually never get any replay.  Anyways I have done the charting my period, temp, ovulation tests and still not pregnant I have one child already and had a miscarriage at 10 weeks in February.   I am really down about it cause I wanted another baby by the time our son was 2 and that came and went!  Everyone says it happens when it happens well i try to think like that but the moment my period comes I am down!  I have no idea when I ovulate I have two apps now and both have me on different cycles!  All I want is a baby!