The transaction log will continue to grow until it is backed up or until it reaches the limit set for it or all the space on the disk. You need to take a full backup of both the database and the transaction log file on a regular basis. You can view the current size by looking at the folder the log is in. You can view the max allowed size by using SQL Server Management Studio. If you have the disk space, you can probably just increase the size limit for now to get things going again. (You may need to restart SQL Server.)
