Dim headlight on 2002 Focus ZX5

The headlight on the driver's side (2002 Focus ZX5) burnt out a little
over a week ago. I replaced it with a new one and now it's *very* dim.
It's difficult to tell that it's even on unless you stand very close to
it. I tried a second bulb to no avail. I tried changing the fuses
(both the ones under the dash and the ones in the engine area) but that
made no difference.

Any ideas on how to fix this problem?

Thanks -

Joanna.