implantation bleeding or no??

alexus

I'm not sure if I have been having Implemation bleeding but I have been having these cramps in my lower abdomen/lower back and I had pink spotting yesterday and today it was more red than yesterday and had what looked like small red mucus balls in it?? also when I lay on my stomach it sometimes feels like a knot??? I have taken an at home pregnancy test which was faint but then at the doctors they didn't show me but said it was negative but to try again....