Bleeding 14 days after my period following a miscarriage?

This is kind of a different Q - and a bit personal. Please bear with me :) I recentley had a miscarriage on May 8th at three months pregnant. I bled for weeks, with no D&C. Finally I had my period on June 16th, and began the countdown to get preggy again :) I usually ovulate on day 18. Hubby & I had a night to ourselves on day 14 ;') And had . Yesterday (day 15) I started spotting blood lightly in the afternoon. Nothing real major, just lightly. I remember when I was pregnant with my son a simular experience happened. I read that it was the egg being fertilized (I think) But I thought it happened later than the day after fertilization. This didn't happen with my 2nd baby that I lost. Has anyone else experienced this? Do you think I am preggy already? Or could this be something else?