is this a signof implantation bleeding.

I had my period last month on time I have taken birth control everyday. i missed one day but took as soon as i remebered. A week later i got cramps and light pink spotting. The cramps and back pain got harder and the the spotting to light bleeding. Very red. watery but not heavy like a period. Well i took a pregnacy test and a blood test and im not pregnant. went to the obgyn she told me to wait. went to the er, told me to take antibiotics and perkset. Now yesterday I finally had a day of no bleeding. today it started back up again. Now I have been bleeding over 10 days. My monthly period is fue around the 1th. could i pregnant or is this a sign of ectopic pregnancy?