A diet largely consisting of squid doesn't do much for the state of your digestive system or your breath, you really don't want to be breathed on by an elephant seal. Most of the time pods are quite fairly restful places in a constant snoring and guttural grumbling sort of way, but every now and then one of the inner most seals decides it wants to go to sea.
I have never had the severe symptoms you describe after a cleaning, that's quite a reaction, but have felt very tired. I chalked it up to emotional exhaustion as I hate having my teeth cleaned. I agree with Wayne Mikie, it feels good to see your name. Hope you are feeling better.
The food or other particles deep inside the tooth become an irritant. The body then creates an infection, or abscess to push out or collect the irritating substances. Another possible source for a dental abscess is dead cells and tissues that are not cleaned away by your body. Every day our body gets rid of dead cells and cellular waste. If your body's cleansing system is blocked, then it may be inhibited in its ability to remove toxins from inside the tooth or around the tooth.