If you didn't keep playing, in your savefile %appdata%/StardewValley/Saves/ (the one with your farmer's or your farm's name), there's a file ended with _old. That's the save for the previous day. If you rename it without the _old and delete the previous one (make a backup copy of the whole folder first), you'll rollback your save a day and get a chance to fish it again (assuming you didn't sleep another night since this bug).
