The episode ends with her rubbing her abdomen and looking wistful. So there is one in there for sure.
Anyway, if it turns out to be monstrous goa'uld larva baby no spoilers please!
I don't the Goa'uld would bother with all this excavation, they'd just go somewhere else.
Is there such a thing as a non-spoiler?
Or the Goa'uld would send a ship, and if the planet was important they'd probably send a new gate with it. The show can be slightly inconsistent on little things like that because the story developed over time. For example, Apophis attacked Earth with only one or two ships, but later we see Goa'uld using many ships ("Thor's Chariot" had at least three) to invade planets with trivially small populations and primitive technologies.
ETA: I forgot how to use spoiler tags. :P