3 days late⚠️⚠️

I've always been dead on with my periods, and this is the first time I've been 3 days late..
My fiancé and I had sex 3 times in July. (ALL PROTECTED SEX W/ CONDOMS & PULL OUT)
once on fertile window (2weeks ago), once 9 days ago, & once 6 days ago. 
period was supposed to come on the 31st of July which was Sunday and it didn't come.
it is now 3 days late and I'm feeling a little sick to my stomach and bloated and I have white watery discharge. but no signs of implantation.. I'm super scared. Has anyone ever been late on their period & NOT be pregnant..