wow, I never heard such things before. Based on my experience in my country, Biology is rather important then Chemistry. Usually biology is isolated from Physics. So, there are two choices, physics or biology? Chemistry is an element between both. I believe, you still have the chance. So in your...
it won't be accurate in 6 days. buy several of the $1 test from the dollar store/tree and test every day from day 9 until your period is 1 day late. Those test are highly sensitive and cheap