At least, it's very unlikely.
In 'King Worm' Fin uses his fears to break the dream world. One of his fears is of the ocean, another of the Lich King. Since 'Evicted' he has faced both of those fears, both with him acting very scared. If King Worm could suppress those fears previously then he could do so now.
The only supporting evidence I can find outside of those two episodes (i.e. not in King Worm or Evicted) is that we see fears flying out of Finns belly button, in 'Ocean of Fear', including the fear feaster. It's possible that in Ocean of Fear, the fear feaster is eating the fears so they don't destroy the dream world. But that's a pretty sketchy argument.
It should pretty clear if they have been dreaming in the next few episodes, by other's memories.
As Enricau mentions, the dreams feature Flame Princess, who isn't introduced until after 'Evicted', and there are several other additions that cannot be explained.
Further to this, characters return in later episodes that would require re-introducing had they just been Dream Figments.