Hi Vicky - I am sorry for your loss.
Yes, you should definitely expect AF to arrive in approximately 14 days. This is the part of our cycle that never changes and is called the luteaul phase. The part that changes is the first part between CD1 and the day you ovulate. For example I ovulate around CD17 to 27 so my cycles should vary in length from 31 to 41 days.
However some people have a shorter lutuel phase, I myself sometimes get AF 11 days after ovulation. If your luteul phase is really short, like 8 days than you need to lengthen it as a short luteaul phase hinders pregnancy.
Also bear in mind that ovulation can happen 12 to 48 hours after your positive opk too so this affects when AF will arrive.
Honestly, not long now if you are waiting one cycle until you try again.
xxx