Grimrock

Im about level 4. My party has 2 rogues, a warrior, and a mage. Right now the front row rogue dies now and again while the back row rogue is using a pike/lance. He had a bow but after 3 shots Id have to run around and get the ammo again. Im wondering if its worth it to restart with 2 warriors, 1 rog...

Is there a healing spell or do party members just heal over time and from potions?