Bleeding...but no cramps

I got a dating scan yesterday and everything was great, saw babies heart beat and dates were pretty much accurate to where I thought I was pregnant, I'm about 9 weeks pregnant but that afternoon I when I went to the toilet the was blood (TMI) clot... I have only had spotting since then, I have no cramps or backache. 
I didn't have this in my first pregnancy so I am worried about it. I don't know what I should do. My doctors are closed on the weekend, I am unsure if I should go to ER cause I am not in pain. 
Other mummies, can you give me advice.