Missed period

I have completely missed my period this month

Massive increase in discharge

I could not have got pregnant this cycle

BUT

i could of potentially got pregnant (dates would work) my last cycle which would put me at around 9 weeks

I can have a late period by a day or 2 but never completely miss one

My question is. If i was 9 weeks along. Would a at home pregnancy test work as i have done multiple and they are all negative