Confused

So frer says test 6 days sooner (its actually 5 days before day of expected period that's not my point though)... so my period is due in 3 days, great, ok BUT according to a chart I found online I may have only implanted yesterday..

This chart is based off when I ovulated... so... I wouldn't get a positive until after my period is due anyway cause it takes 2-3 for hcg to build up...

I am not sure what my question is really.. just a rant cause I am kinda confused by the whole testing early?

Disclaimer my cycle is really out of whack maybe that's why my dates are whack a doodle?