It does sound fun, grim and gritty. The first encounter sounds very tough but they overcame it. Fair? It seems fair to me, but a diaglo raised a point above that makes me "wonder"
and a pack of wild dogs outside. meant we couldn't run still
Personally as a DM this would not have been an barrier to players running away if they are normal wild dogs. As animals wild dogs are interested in the easiest meal possible. The dead lizardmen more than fit the bill. Given a lizardman probably weighs 80 kg plus, and a hungry wild dog eats about 3% body weight a day, assuming a 40kg wild dog (very, very big one by the way) were talking about 30 dog/days of food per dead lizardman assuming only about 50% is edible to the dogs.
What does all this mean? It means let the dogs feast on the dead. They'll be stuffed and won't bother the PCs, and most likely they'll head back to their den to feed their pups and relax after the sucessfull hunt. If there is still food, they are likley to come back to finish the corpses. But they won't be the only ones, other scavengers and predators will arrive. They of course are interested in the easy food. If the PCs get out of the way they will leave them alone. Actually, the corpses will probably draw local scavengers and predators to the easy food and away from the PCs as they try to get away.
In addition, animals have territories. If the apex carnivores (e.g., wild dogs, tigers, etc.) get their fill on the corpses the party is not going to encounter another pack of hungry wild dogs until they get out of the first pack's territory. The bottom line, after the wild dogs showed up would be the perfect time to run.
Another question is if the players didn't know this wouldn't the PCs? If you play that way (i.e. character knowledge makes a difference in info conveyed by the DM), I'm thinking a druid would certainly know animal behavior and the DM could drop him a hint about such. An example DM narration,:"The dogs gorge themselves on the corpses. If they are normal wild dogs, as a druid you suspect they will now go back to their den and rest for a day or two. You doubt there is another pack nearby as the territory of such a pack is rather large."