when can i test?

i know 8/9dpo is a little early to test but seeing that it’ll be 6ish days before my missed period would that still be too early?

I O’d friday the 13th and my period is due the day before glow says it is.

first month using opk’s which confirmed a positive opk on CD14 and had three days of spotting and now i’m 6dpo, had brown spotting but only when i checked, and my CM (tmi) is a little creamy yellowish? i have these dull cramps/twinges. my boobs don’t feel like anything. slept from 2am-2pm and it’s 3:30 and i’m ready to go back to sleep. been irritable and emotional on and off the past two days. i thought i was last cycle but i think i stressed myself out so much hoping i was, i ended up being 20 days late. any comments or opinions help and feel free to share your stories!!