What Causes Vaginal Spotting During The First Month Of Pregnancy?

my last period was on January 20-2015 and I took about 10 home pregnancy test they were all very fait line but all positive I started lite bleeding today and while bleeding it still shows positive but blood test at the hospital says i m no it showed a 5 so am I pregnant or not im so confused and me and my husband are excited to really no if I really am my breast are sore I puke morning and night nausau all the time please help me figure this out we have four other kids as well my name kim