Close to ovulation, a bit confused

So I’ve been tracking my symptoms around my fertile Time right become ovulation and eve has been pretty accurate on the day of ovulation. Last month I was positive opk three days before I actually ovulated. Unfortunately I started my period early that cycle which brings us to this cycle .. I’ve noticed my sex drive being increasing and my mucus is more watery. I’ve also noticed lower back pain, pelvic pain (mild) in both sides. I’m having some diarrhea and feeling very nauseous. I usually have a lot of bloating and breast tenderness a few days I actually ovulate. Is it normal to feel nauseous around this time in my cycle? Can any relate? When is it best to have time intercourses ? Now or when I get a positive opk?