not starting--alarm & flashing lights on 2003 Toyota Camry

Just last 2 days when key is turned alrm blasts, lights flash. Trying again, finally starts 135,000 miles 2006 battery--does it need replacing?

Asked by for the 2003 Toyota Camry
On my impala I had to change my ignition switch, to solve similar problem. I am not a expert though.