late !!!!

Caitee
I know this probably isn't something I should be worried about but!.....
Normally my period arrives about 4 or so days before due date 
This time it's not come not even 3 days after..... I'm not stressing about it I'm just worrying & ive got acid reflux so wouldn't be able to say wether am having night sickness I'm just confused I guess anybody else been like this