I Have Been 9 Weeks And 3days Pregnant , I

I have been 9 weeks and 3days pregnant , I was very well before going for antinental but when I went,they did ascan and the doctor said that something in liquid form was forming near the uterus so she gave me amplicox 500mg to take 4times aday but when I took the first 3times I started bleeding, the more I took the more I bleeded until I got amiscerrage, so I would like to know what caused it if they say that ampiclox is not harmful to early pregnancy . Thanks