Did i test too early?? Please help!


Hi all , i miscalculated when my period is actually due and I’m due to start af in 2days on the 18th when I originally thought I was going to start today :/ oops ..so I took a test today but it was negative and it was a cheap test not a clear blue or first response test so I’m unsure if it would detect it this early or not ? Please can someone tell me if it’s possible that i could have just tested too early or if they got a positive at this point ? Or if I I just tested the right time and it isn’t our turn this month ? Sorry i know i could just wait to find out but I really need advice on how early to test please thanks all :) x