No, that’s not right. Your script is located at http://www.olliedaw.co.uk/wp-content/themes/Daw%20Refrigeration%20Milk%20Tanks/js/excerpt.js and you’re enqueueing http://www.olliedaw.co.uk/wp-content/themes/DawRefrigerationMilkTanks/js/excerpt.js … those are not the same file!
This happens often when you have spaces in your file names and directories. Either remove the spaces or explicitly escape them as %20 when you queue them with wp_enqueue_script().