Spotting and I'm so nervous

So I just felt a little extra wet so I went to the bathroom and noticed that I had some blood in my underwear. I started to freak out of course ... called and spoke to the doc on call but all she said was that I have to wait it out and see. She says if I'm not cramping really bad along with heavy bleeding then I shouldn't worry just yet. I'm so upset... I don't know what to do. I am 11w 1d and this out of the blue is so heartbreaking. How could this be happening to me right now? Why?