Heavy spotting

Gabriela
Hello ladies! 
  I'm 6w2days preggo and I've had some heavy spotting going on... Also when I went to pee yesterday I had a clot that was the size of a grape come out.... I'm freaking out and I'm so nervous, I don't think that's normal and I hope my baby is ok!! I went to the ob last Wednesday for an ultrasound and baby is to small to see anything... But my uterus and ovaries and everything rose looks good.... So I'm going back this Thursday for another ultrasound hopefully now we will be able to figure out why I'm bleeding as of now it's a waiting game and this is all that's on my mind and I'm thinking the worst please pray for me and the little peanut... Has anyone else experienced this?