Ahh!! Just took a test!

I just took a test and there is an extremely faint line on the pregnant side that I'm not even sure if it's really there! I tried taking a picture to see what you guys think but it doesn't show up :( I'm so nervous in the most excited way! I just want to know for sure!!! Does the darkness of the line depend on your levels of whatever it is the test detects? I'm supposed to start my period Wednesday so I'm still a few days away.