Spotting in the 1st trimester. Help!

I'm 7w1d and I began lightly spotting yesterday. It's brown, no red has been seen and it's only when I wipe after going to the bathroom. My mom also had spotting during her first trimester, as did my Mommom but I can't help but be anxious and I'm probably slightly paranoid as well. My first u/s was at 6w1d and saw the baby and the heartbeat was strong at 167. Anybody have 1st trimester spotting as a norm and had healthy pregnancies?