Almost 5 weeks and bleeding?

I've been testing positive for a week now but only on the first response tests. My period was due last Wednesday but I woke up this morning and had bright red blood when I wiped. My heart broke :( I decided to go to the ER and they did a urine test which confirmed no pregnancy (but then again the dollar store tests are still "negative" too). I'm not having ANY cramping or clots and the hospital drew blood but didn't test it for anything other than my Rh, they also didn't do an ultrasound but diagnosed me with a complete spontaneous abortion. So I came home and started reading, from what I have read miscarriages normally come with pretty heavy cramping and clots. I also read that if your body doesn't have enough hCG you could still get your period and sustain a healthy pregnancy. I still "feel pregnant" because my boobs still hurt and I don't find food that I liked 3 weeks ago appealing. Anyways I don't know what to do... Has anyone had a miscarriage without cramping? Or bleeding (not enough to even use a pad but maybe just a panty liner) while pregnant? I'm just so confused and very upset :(