5wks, decreased pregnancy signs, brownish discharge

Nicole
I'm 5 weeks today. 32yo, first pregnancy. I had been feeling pretty nauseous weeks 3-4. Over the past 4-5 days, my nausea has disappeared, as well as my fatigue. My breasts had been very sore, but I noticed yesterday they weren't as sore.  Two days ago I had a scant amount of brown spotting. This afternoon I developed mild period like cramps for the past two hours and just noticed brownish/whitish discharge which wasn't there a few hours ago.   Also, last night, I had a dream I had a miscarriage. 
I'm feeling really worried and sad now.  Has this happened to anyone else?