When i should i test?

Right so glow says af isnt due until friday but it can come any day from tomorrow as last month i had a 25 day cycle. So yesterday morning I woke up went to the toilet and when i wiped there a a small amount of brown discharge so i though af was here only Ive only be getting tiny amounts of brown discharge since yesterday morning. Also last night i started to get a sore throat and chest, today is still the same and my voice has started to go funny 😩 should i wait until after friday to take a pregnancy test or could it show now if this is implantation bleeding? Sorry if i sound dumb and thanks in advance x