My Husband Has Severe Abdominal Pain On His Right Back

my husband has severe abdominal pain on his right back side. it started last night after supper and kept him up most of the night. the pain went away this morning, but tonight it started again. after eating supper again. is there a need to go to the ER or is it ok to wait and go to the Doctor tomorrow? he doesnt want to go but i know i must make him go