Where have all the fish gone?

Having fished hard for 3 nights this week I could only manage 1 small sea trout of 1.5 lb and a small brown trout! Is it that there aren't any fish around or is it that they are there but don't want to know? Even more disturbing that despite the weather being generally mild and overcast I didn't see a single fish jump or hear any surface activity in a total of 15 or more hours on the river! From my records July is the best month for sea trout by far but this season is looking very doubtful on that score. I feel that I fished very well. I threw long straight lines and fished very carefully all the way down the flats; below the hedge and in my pool but to no avail. Is this unusual? My memory is terrible but probably not! I'm just hoping and praying that fish start running very soon so that we can all enjoy a little sport on the river this season!