It is pretty common and everything could be absolutely fine. Lots of women spot in early pregnancy for various reasons and have healthy pregnancies. Are you cramping? Typically you need to worry when you are bleeding real blood, red in color and are also having bad cramps.
Although there isn't reason to panic, I would call your dr (or the on-call if there is one) in the morning to let them know.
*Enter lurker* I had some spotting around the same time. DD is almost 4 Put your feet up and drink some water. It may or may not make a difference but any time something seems off, taking a break is a good bet. *lurker out*
Totally normal, but for peace of mind you can call your OB. I had some brown spotting a few times during my first 10 weeks - mostly after sex or an internal ultrasound. It is normal and is going to happen. My OB said his wife bled every single day for 20 weeks. Every. Day. I'd go nuts!
Re: spotting
Although there isn't reason to panic, I would call your dr (or the on-call if there is one) in the morning to let them know.
Good luck :-)
What Are Your Thoughts on Tap Dancing Penguins?