Faint Positive after Period??

I started my period on 1/12. It’s was shorter and lighter than normal. It lasted about 3 days with the first 2 days medium flow and the third day light flow. Had some cramps but not as severe as normal. My temps have still be high, never dropped below the cover line. Today I decided to just take a test because I’ve been feeling tired and a little off. I didn’t think it would show anything but figured it would ease my mind. I got a vvfl this morning. Is that accurate? Or maybe the test is defective?