I can't say anything about Lithium or its side effects, the symptoms however lead me to consider the possibility of an allergic reaction.
A relative of mine who had the first two issues and couldn't find a cause narrowed it down to a problem with diet, a problem with stress or metal poisoning from the materials in their cooking implements - pots, pans and such.
They've changed their diet, eating only one type of meal at a time - meat, carbohydrates, fruits, veggies etc, they've found more ways to wind down and stuck to what they liked and worked and they changed their cooking equipment. So far, they haven't had an outbreak in about half a year or so.
Without a cause to be found and if your doctor agrees it might be an allergic reaction, you could try to narrow the cause down same as my relative did. I hope this information helps.