Hi welcome to Health care magic forum. according to your quiry the pain in the right lower abdomen started after treatment with valacyclvir, for shingles
. valacyclovir didn't have side effect like abdominal pain
, if at all there it should be in the upper stomach. If upper stomach pain is there also it can be reffered to the lower abdomen.
The pain if due to shingles pain should be there before treatment is started. So it is ruled out.
The pain appears to be due to renal colic
, or appendicitis
so i advise you to consult a surgeon for diagnosis and treatment. You may need to have U.S.scaning along with clinical examination and routine tests for confermation, and treatment.
Wishing for a quick recovery and thanks for calling.