Cheap Amazon tests and 5 days late

Carrie

I’m 1-4 days late since my cycle will sometimes vary a couple days. My boobs have been intensely sore for a week now, which is out of the ordinary, feeling nearly nauseous and having some cramps. I tested today with 2 Clinical Guard tests from Amazon and both were negative. I wouldn’t really think about it if I didn’t have all the symptoms too. Are those tests accurate?