I stumbled on Shadowmirk long before the storyline required me to go there. I got far enough into the dungeon to obtain the potion of Ogre Strength. I didn't complete the dungeon, figuring I'd come back at some later time.
In the meantime, after wandering around with the Ogre Strength potion in my inventory for a long time, I finally sold it because I couldn't find a good use for it and I needed the cash.
Now that I am back in Shadowmirk near the end of the game, I realize I now need that potion to get to level 2. I checked all the stores and none of them have it. I don't even have a save-game before that point anymore.
Am I screwed?