Wierd bleeding need help!!

Samantha
So i am 8 weeks today and sunday i started having some brown bleeding/discharge I called an on call nurse and she told me to go to the er just to get checked out. So I went they did a blood test an ultrasound and a vaginal ultrasound and a urine test. Everything came back normal, the doctor said the baby had a good heartbeat and my hormones were perfect and that it was probably late implantation bleeding. Well it has still not went away and has even became a little heavier to were i need to wear a small panty liner. I have had some light cramping in the front constantly but nothing seriously painful. Has anyone else had this or know anything about it??? This is also my first baby. Thanks for the help