Car won't turn over.

My 2004 buick century wouldn't start so I replaced
the battery this morning.  The initial attempt to
start the vehicle with the new battery was very
slow like a low battery but only turned over twice.  
It did not click indicating a lack of voltage but
instead bellowed smoke from the starter area
smelling strongly of copper. I replaced the starter
and the following attempt resulted in a backfire.
After the backfire it cranked almost normally aside
from a high pitched squeal similar to a train
applying brakes. Can anyone tell me what the hell
is the next feasible possibility?