Spotting after 6 days of missed period

Hi All,

I need your suggestion..

My cycle is mostly 27-29 days. I am ttc. Last period I had was on 7th April. glow app shows I am 6 days later for my period. I was planning to take a test tomorrow, although sadly today evening I started spotting. It is watery with some colour which is for sure not red.

I read somewhere that implantation bleeding doesn't happen after missed period. Can someone tell me why I am spotting then? Anyone else experienced similar situation? Please reply, I am panicking 😥😥😥