after implantation you will start to produce hormones that are detectable on a hpt for pregnancy
. but it may not show until you are late for your period
. there are a few that get positives before, but waiting till you are late is the best. good luck and hopefully i havent made your head spin, and if i said something crazy forgive me im tired!! lol. get a book, or google the heck out of this stuff. you will find everything you need to know.