when should i work out my due date from eo confused lol

hi new to forum so not sure if i have posted in correct section or not??

i had what i thought was my periods on march 25th to march 30th im usually bleed pretty heavy but its was only i light period
i did my first pregnanacy test on sat 9th april and have taken one everyday since at diff times of day just to make sure and they all test postitive,
im due for my next period 23rd april so should i class my last period of as bleeding to do with implantation of egg and go from my period before that????
sorry rather confused lol dosnt take me much haha
cant get into to see my doctor for 3 weeks
thanx

How long are your cycles usually? When was your last "real" period?

You calculate from the beginning of your period, you can use a due date prediction calculator like this one Due date calculator