How to fix moisture problems in shed?

I have a 16x44 omish wooden shed. The building is setting on road gravel , that we put down. I have insulated the walls and they have been drywall. I sealed the floors with sealant, and the sealant is still sticky, not quite dry,day 3. The mud in the corners of my drywall, is still not dry, day4. I still need to paint the walls,but was advised not to, right now. What to do? I do have a dehumitifier. I do have a heater and there is electric. All I'm doing now, is praying the room dries in the next couple of days. The only thing I haven't done is the ceiling. It's raw, but I do have a 3 foot vent in the ceiling, for air flow.