Could i have miscarried?

Ok so my periods have been all over the place last few months...yesterday morning had strong abdominal pain couldn't move then had spotting plus more pain again today.was this Implantation bleeding or miscarriage...my blood is dark brown...not red...I did have period 6 days ago which I thought was a normal period...had 2 diff pregnancy tests today both positive...I have doc app tomorrow...am I still pregnant...??