Testing - NEED HELP!

Okay ladies - although I Have been TTC for over 5 years now I have no actually taken a test in a VERY long time. I figure it's such a waste of money. If my period is late more than week that's a different story. Anyway, I have been having EXTREMELY sore boobs the past few days. I cannot remember how early I can test. I am approximately anywhere from 6 or 8dpo. I took a test this morning and there is a VERY VERY VERY FAINT LINE in the window that we all need to be pregnant. I don't know if I'm just seeing things or losing my mind because I want this so bad. Any suggestions? I know I need to wait a few more days. My period isn't even due for another week so I'm thinking it's nothing. What do you ladies think??