help!

Usually my apps are on point when my period starts. A few said I started yesterday, a few today one says next week.(it's a little irregularl by a few days or so) I haven't had any PMS symptoms besides some cramping and today more cramping, boobs are starting to get a tad tender(only if go up/down stairs&press on). But today along with the cramping I'm feeling now, Im having a sharp pain on my left ovaries. And This morning I felt discharge come out which I though was af, but it was like a creamy watery white discharge. It came out that once and I haven't noticed it since. I took a test two days ago and it was a bfn. I don't think I'm pregnant or again feel any symptoms really. I'm 16 dpo. I just don't feel like this before af, I usually know when I'm starting . Anyone else experience this? Am I just expecting af next week instead?