Thank you for the feedback! I did intend on having a station were you could spend ingots to regain health, but it wasn't ready in time. For sure i'll be rebalancing the game as soon as the jam is over, to have a more subtle curve.
If you want a tip, try putting a second iron ore in the furnace while you remove the first. This way, it should be ready to pick up as soon as you finish the first sword, allowing you to continue the loop without stopping.