possible miscarriage ?

it started last week light bleeding i think it was like a browny red , i woke up next day with a really achy back still bleeding i got on with my day , on the sunday night i was having bad cramps and pain in my left side i went to the emerg docs and they give mi antibiotics for water infec i woke up monday to blood and blood clots and been havin them eversince on thursday i went bk docs and the rec give mi a bottle to pee in , still bleeding and blood clotting i was drinking loadsa water through out the week , on satday it was really bad crampin and i could feel blood clots comin out off mi so i went doc thinkin its a kidney infec he checked mi over and said its poss n gave mi antibiotics i bin having headaches and feelin dizzy and like fainting , the bleeding as not bin as heavy their still blood even on tissue this morning when i woke up this bigish black thing came out and blood , went on agen their were pieces off red clots , bin toilet agen its clear with jus lil bit off blood and on tissue , i only relised when my mum said culd i b pregnant and mis carriagin i sais no but mi and my bf had un protected the week i was off the pill , i told the doc no aswell , i ve got an appointment tomorra to get sum more contraception pills shud i tell my doctor this ? what will he do , ive had diareah to , i felt as tho i was dying , culd it have bin a mis carrage ? plz help thanks xx