Does Pinkish Vaginal Bleeding Indicate Implantation Bleeding?

We are trying to have a baby... I am not supposed to start my period until Sept. 6 and am usually late. However, yesterday I had a small amount of pinkish blood and a little clot when I wiped. I thought it was too early to have my period since its only been twenty days. I put in a tampon anyway. A few he's later I take it out and it was clean. The same thing happened to me today and was wondering if this could be implantation bleeding?