hi,thanks for query.What I understand from your question is that you were supposed to have your periods on 25 the dec
and you did not had till now.You had relation with your husband in last phase of your cycle,this are normally non fertile days if your cycle was regular before.Please go for pregnancy
test and confirm the result.In case of negative result please see your doctor for some medicines which will leads to withdrawal bleeding.After that please use some form of regular contraception
to avoid such incidents again.
wishing you good health.