Needing advice

I have taken 2 pregnancy tests over the last week/week in a half, both showed to be positive.  Today I noticed a little bit of bleeding.  It was brownish in color which I understand to be old blood.  My question is usually when would implentation bleeding occur.  My last two pregnancies ended in miscarriages.  The first was at 16 weeks, the second at 10 weeks.  My ob/gyn doesn't think there is a problem due to the miscarriages occurring in different trimesters.  Could this be a sign of another miscarriage?  I have a healthy 10 year old with no complications what so ever.

[alaysha]

Brown blood isn't really something to worry about in early pregnancy since it could just be blood left over from in there. Implantation bleeding usually happens about 7-10 days BEFORE you're period is due. I know how scary it is being pregnant after a miscarriage but honestly this doesn't sound bad to me. Now if it was bright red blood that would be worrisome but light pink or brown blood can be normal.