electrical problem

While changing the battery in my 1997 geo metro, by mistake I conected the wrong side terminals on the battery, now I don't have any lights nor I can start the engine. Did I burned something really bad?
What can I do to solve this problem.
Thank you guys for your help.
Jim

Hopefully you just blew a fuse, and not damaged your ECM. Search the forum as I remember someone else did the same thing recently, but I don't remember the outcome.