First Check for any open transactions in Tempdb by running below query.
DBCC OPENTRAN
if you get below results means,start to shrink the Tempdb files.
dbcc opentran
--No active open transactions.
--DBCC execution completed. If DBCC printed error messages, contact your system administrator.
dbcc shrinkfile('tempdev',sizetoshrink)
eg.
dbcc shrinkfile('tempdev',10)
That's it.
Regards
Kumar
http:\\Sqldbataskwithkumar.blogspot.com