In those cases is recomendable to restart the game or Pressing Esc>Backup Load, then, try again.
Exactly how it was? Did you make the Kelpie follow you by whipping him or by starting/canceling sex? (because only the second is counted)
If possible, share the save file here so I can check it.
Also, if you ever find a Game Breaking bug, try doing the Backup Load and, or download the SaveFiles on the OP, there is a folder with Story Mode check points, so you can restart where you left.
Money certainly is a problem in the beginning but it becomes useless pretty quick.
You can earn a lot of money by finding Treasure Chests over the world, there are many of 500 or even 1000 coins (If you have problems trying to find them, ask the Blacksmith guy on the sheep zone).
Prostitution gains increases in relation to the amount of times you had sell yourself, at the beginning is pretty low, so it's not a factible money source. It's better for seeing sex anims with the Futanari mode.