Sitting in the parking lot, FREAKING OUT!!!

I'm sitting in Walmart parking lot having a mild panic attack! I'm 4 days late, and am usually VERY regular. We've been ttc for 26 months though with no luck, so I'm scared shitless to get my hopes up for nothing. I've decided to get one of those cheapie 88 cent tests & see what it says. Don't wanna spend money on anything more expensive than that, for fear I'm about to be let down anyway. Needless to say, I am FREAKING OUT & don't really want to test at all, but I wanna know why my period is MIA! PLEASE wish me luck ladies! I'm so scared I'm about to be disappointed AGAIN. ARRGH! I hate this feeling!!!