condensation/shed

[jeffpick]

Hi all I built a brick shed in my garden with a single brick course no cavity and put in a concrete floor with a membrane under it. I am having a small problem with condensation/ damp. I put airbricks in just above the brick damp course and a few at high level just below the roof this made it slightly better. But after reading the forum I think I may have a problem with the joint where the concrete meets the brick so I'm looking at sealing this up then putting a wooden suspended floor and a stud wall around to create a cavity. Shed has a freezer and a fridge in. This usually has condensation on the door and any tools in ther start to get surface rust on them.
Concrete floor comes up to the level of one brick below the DPC in the brick work. Wooden floor woul go above the DPC.
Am I on the right track here or do I need to do something else.

Cheers Jeff