how long is "normal"?

So I posted before about having brown spotting, I know it's not uncommon and I had an ultrasound Friday and everything was good (6+4 at the time, and baby's heart rate was 132). In 7 weeks now and the spotting has been going on for a week now. There was a day in that week with no spotting. It's not a lot, it's just 2 or 3 times a day there is a tiny bit of brown discharge on my panty liner or a tiny bit when I wipe. Is it normal for this to happen for this long?