Hi. I'm Having Very Sore Nipples They Are Also Darker

Hi. I'm having very sore nipples they are also darker in color so is my areolas my breast are heavier and fuller I am always very sleepy I have lower back pain my period is late I had sex on the 31st of last month close to my period that was supposed to start on the first week of this month I had brown and light pink and even clear discharge I took a test last Monday it was negative and I took one this morning it was negative so idk I knew missed a period for this long get my period every first week of each month..can someone tell me what's goin on?