A little worried

Toni
I found out 2 weeks ago that we are expecting #5 (#4 I miscarried) and the apps all said I was right at 2 weeks. Now that I'm 4 weeks I started having brown discharge. Is this from implantation or could I be having an early miscarriage. Anyone else having this or is it just me! I'm going to go get another PT tomorrow and see if it's still saying pregnant. I'm a little worried!