There is not much to do after hitting the gong, and you can skip a fair bit of it.
Chasing Josie... techniques for defeating Josephine
If you drop both teleporter pyramids on the ground a few feet from each other and click on one, do you get the same error? That error usually means you have both of them in your inventory or left one in a container, but a couple people have had them simply stop working.
The telporter stones are not essential for the end of the game, but would be handy to have if you need to return to the trader for more potions or to look for better equipment, etc. The teleporter pyramids are replaced when you move on to the wastelands, so you can simply leave them behind when you hit the gong, and pick up the new set hidden just north east of where you appear. If you have one or both in your inventory, the replacements get put in your inventory.
You can check merchants looking for one handed swords, or search the forum for topics about the best swords consistently in the game. If you have not completed the holy item quest, the Nobleman's Sword is one handed (
Gathering the Holy Items and the Sacrifice), though you may want to consider the amulet, as well. After you hit the gong you can find the Sword of the Gods, potentially the best one handed sword in the game, in one of the abandoned houses.