missed my Nov period but not pregnant?

[Ash80]

My ds was seriously ill In Nov, i guess thats why i missed my period.I then got my period mid Dec.My dh are trying for a baby and it is now mid Jan and i don't have my period yet.
Im a little confused, as i got my last period mid dec, should my next period now be mid jan.......does my ovulation cycle change cause of the missed one in Nov. ( i usually get my period at the end of the month)??

I too had this recently I am usually so regular 28 days but a couple of months back had a skipped period by abour 3 weeks and was confused as to when I was ovulating, I am guessing though that you begin over and count 14 days from beginning of lmp and take that as ovulation date??