Late period...

I'm  3 going on 4 ish days being late. We've been trying for a while, this month we used preseed. I'm TRYING not to think to much into symptoms and stuff like I usually do and then get my hopes up. All I'm getting is white discharge. But usually my period is on time or early. I'm scared to take a test, I'm afraid of a negative :( should I go ahead and take one or wait it out?