What the heck!

Autumn
Me and my husband are TTC. About a month ago I tested and we got a faint line. And then we tested again and it was a negative. About a week later I tested and we got a faint line. This month rolls around and my AF is late by 2 weeks. I test Sunday and the first one was negative, but then I tested the next morning and we got a faint line again. Am I seriously just getting all the default test or what. I am 21 and I was on the depo shot for 2 years. And I've been off of it for a year now. I'm getting really discouraged.