Miscarriage or ectopic? Please help!

I went for blood test & ultrasound.  The 1st ultrasound the dr. thought he saw the start of the sac (3 weeks), my HCG was 780.  2 days later HCG was 2100.  I had strong abdominal pains the next morning that I thought were gas pains. The next day my HCG declined to 1400 and they could see no sac in the uterus. Bleeding was dark-brownish, but now 3 days after the decline in HCG blood is dark red.  Did I have a miscarriage or an ectopic?  

This was an unplanned (but not unwanted) pregnancy.  At the time I conceived I was taking diet pills (phentermine 37.5 mg) and a new medicine to stop smoking (Chantix)....not to mention Saturday and Sunday I received 2 large doses of Demerol shots.  Also before Saturday morning I had absolutely NO bleeding or pain. I ironed clothes, mopped, cleaned bathrooms, etc. and began to hurt and spot brown blood, which led me to take the pregnancy test.  Do you feel that all of this could have possibly contributed or directly caused me to miscarry.

[mommieof20607]

with all the meds and wot not could possibly have caused you to miscarry.....but if u havent passed anything(blood clot or tissue) u need to go to the ER to have a DNC it will help...but it will also not feel too good but its needed b.c if u dont it couls cause a bacterial infection and make u steril...