This is normal. After the dragon armour and heart are forged together, you can buy back the originals. This way if you don't re-load to get good equipment and end up with something crappy, you can still go back to the original. Also, the head of the warrior's guild does not recognize the heart of the dragon in the armour; if you get the armour forged before completing the second test, you can still buy back the heart to join the guild. Similarly, you can buy back the eye of the cyclops after the first warrior's guild test.