Late Period.

Erin • I'm Erin & I'm 27, I use eve for cycle tracking and Q & A - Mum of a little boy & little girl and engaged! 💖
Hey ladies, 
I'm currently 3 days (going on 4 days tomorrow) late. 
I'm just wondering if this a common thing?
I'm trying not to get my hopes up as my partner and I are trying to get pregnant (have been for the last 6 months, not successful yet). Pregnancy test was inconclusive.  Nothing appears out of the ordinary other than this. 
Any tips, suggestions or ideas? 
All feedback welcome.