Honestly I think your TTW would be at an end, given the dates you have mentioned. When was the 'first' day of your last period? If the last day was the 17th Nov, I am assuming the first day was around the 12th or 13th. IF you cycle is a standard 29day cycle, that means you should be all good to test around now (ie, your next period would be due around now). Of course if you wait until christmas, you will definitely have the right result for sure - but if you don't want to wait that long for an answer, a HPT would be pretty accurate now.