Try to relax a little bit.
If your previous cycle was regular,then you dont need to be extra worried.
Your period is delayed due to extra mental stress
or tension as your marriage is coming soon.
Try to cool and relax yourself and dont think much about your period.You get your period in time.
If your period is delayed by more than 2months late,then need to investigate properly. It may be OLIGOMENORRHOEA due to some condition like PCOD
, Mental stress,Hypothyroid, Anorexia
If you need extra consultation,then contact with me. My Id firstname.lastname@example.org
All the best for marriage.