Can't connect to the db

Hello every one I was using my db with an application in perl, but 
something occurs with the application and the pc got frozen  and I had 
to restart my PC, when it boot again I coudn't restart the psql service 
when I do the psql mydb it shows me the next error, the error is in 
spanish but it says something like:
   psql: can't connect to the server: there is no file or directory
   is the server running local and accepting conecctions in the Unix 
domain socket «/tmp/.s.PGSQL.5432»

do I have to reinstall again the postgres or can I do something else?