When to take a pregnancy test? Help

Starting to get confused. So had my period on the 2nd while the 7th of this month. Due on AF today but had no signs and no bleeding whatsoever. Been urinating a lot more than normal, never off the loo at minute, with occasional sore breasts that's it. Had a pink discharge after sex a few days ago but nothing since. Took a test today and it was negative but I did it during the day, been told to do it first thing in a morning. Could I just be late on my period or testing too soon? Heard hormonal levels may not be strong enough to show on a test, should I test first thing in morning or wait? I'm on CD21. Can someone help me or give me some advice please. Trying myself crazy reading articles haha ?✨?✨