12dpo question

I am 12 dpo and noticed today that the lower walls of my vagina are really firm, but the upper part and cervix are very swollen. I also have a watery/milky discharge and my cervix is high. Today is 5 days before a missed period, but I tested anyway because I'm impatient. It came back negative. However, I swear my nipples look slightly darker and I can see blue veins on one breast. I have also been extremely tired all week and have had mild dizziness and nausea the past two days as well. Are any of these signs that others have noticed in early pregnancy, or am I just tricking myself into thinking it?