brown spotting can be very normal. it happened to me a couple times during this pregnancy and everything still looks good. the cervix is very sensitive during pregnancy and anything could make it bleed (sex, excercise, etc). it could also just be implantation bleeding.
BUT, if you notice that the spotting gets heavier, where it turns into red blood, with cramping or backpain, then it may mean a chemical pregnancy (I've had three of these

). for me, the spotting was only there when I wiped, I never noticed it on my underwear or anything, and it was there for about a week before the miscarriage occured . what I noticed differently about the spotting I had during this pregnancy versus the chemical pregnancy, is that the spotting got lighter rather than heavier through the days.
dont lose hope, even though it may mean impending miscarrige, it could also be VERY normal. If you have a good doctor, you should be able to call to get ur hcg and progesterone levels checked. You could also just wait to see what happens
sorry I am not the barrer of all positive news

. But I remember when I used to spot, I would virgiously search the internet to find out what I was going through (both good and bad). so I just want to be honest to help anyone going through this.
wishing the best for you hun. hugs