Help a girl out? I’m desperate 😞😭

So I’m a little lost here...I been tracking my period, and using ovulation test strips for the first time, Sunday June 17th I got two solid lines and BD, however I have 3 different apps to help with it and they all say different things, throwing everything I’m writing down off track😞 One says my cycle days are different( Like the 17th is CD21 but says 20 and the 18th is CD21 which the 17th should be 21& the 18th should be 22). So confusing 😱😰 So my question is: How do you ladies keep track of this all? I’m new to tracking and using the strips, the body temp, tests &all; that😕

My cycle length is 33 days, My period lasts about 5 days, I’m regular though I do have endometriosis & pcos. Any advice/experience or anything would be greatly appreciated🙏 and if anyone doesn’t mind...maybe some tips to help a girl out ❤️ Thank you😊