Hi all. Sorry I know I’ve posted a lot just confused.

Basically I starting testing at 7/8 dpo with clear blue, early I know but I had a faint but visible blue line. I’m 10dpo today and have tested every day since 7dpo. So I have four tests. Yesterday 9dpo, there was no line from what I could see on the test, so some people said chemical. However, I’ve tested today at 10dpo and the line is starting to appear again. Is this just the famous clear blue evaps or a chemical? I want to test with a first response but can’t get them any where near me only off amazon. Thanks all, photos of the tests in order below x