AF 3 Days Late a little TMI

Just last night I got the tiniest bit on pinkish/peachy discharge, and it was only there when I wiped. Clean undies. Early this AM I had a bit of brown discharge.. Which indicates older blood, right, implantation bleeding perhaps? Just a little bit ago when I wiped there was the tiniest bit of red, and then a little redish/brown. But I'm feeling pretty freaked out by the bit of red.. I just really am in need of some peace of mind. We've been TTC for 7 cycles now. I tested yesterday AM and it came back negative, but if this is implantation bleeding that means I won't get that BFP until after baby attaches due to low HCG. Based off of my last period, I would've conceived around the 3rd.. HCG levels won't be detected until around the 12th-14th day after conception, which would be tuesday. Anyone have any similar experiences and ended up being pregnant?