Chemical pregnancy?

[myworld_18]

This my be a little tmi but I'm curious. I have had a miscarriage before when I was 2 months pregnant and got pregnant again and had my son. But today I was spotting a little and after I went pee I looked down and saw this chunk of something with a circular reddish sack connected to it. I had my period a week ago but it was 3 days late and it only lasted a couple days. I took a pregnancy test because I started having the same symptoms I had when I was first pregnant with my son But it was negative. Its been almost 3 weeks since I've had sex. I'm not really worried but I'd just like to know if it's something I need to go tell a doctor or not. (my fiance doesn't know about it) any advice or comments would be greatly appreciated