Spotting?

I found out I was pregnant last week, and I'm roughly 8 weeks. I've had spotting for the past 8-9 days, and was just wondering whether I should start to be concerned, as I've heard it normally only lasts a few days. It's a brownish colour, and it's very light (the flow). Should I contact my doctor or is this completely normal? This is my first time being pregnant so obviously im extremely anxious. Thank you x