Spotting???

I've been ttc for a year and a half. Got pregnant in The end of December but lost the baby in February. I've been ttc since then. Three days ago I spotted though I was starting my period since it was three days early. Took a test came out - so I put a tampon in thinking ugh another month trying. But when I took the tampon out there was only a spot of blood. Dark blood too. The next day it did it again so I repeated the same step and it happen again. I decided to have sex last night since I didn't start my period. And only bleed a little. Today it the day I'm suppose to start my period but now there is no sighs of bleeding. Was that implantation bleeding?