When I pick up Brown mushrooms they never appear in my inventory.  Due to this I can't make a potion of weakness and cure the villages I have been collecting, Its really very frustrating.

I was able to pick them up a few days ago, but after I harvested a giant mushroom they just all vanished from my inventory, and now when I go to my mushroom farm and pick a little one, they never show up in inventory, I can strike them and have them setting but if I touch them they just vanish.