Implantation Bleeding

Ok ladies I need your help...I have just given birth 5 months ago to a beautiful baby girl. I have had normal regular periods for 3 months since I’ve had her. So my period isn’t due for another 10 days but early this afternoon I went to the bathroom and when I wiped there was just a little bit of very dark brown stringy discharge. Could this be implantation bleeding? I’m so confused because me and my fiancé have only had sex once since my last period. Someone please help me figure this out.