Can you have a problem with your uterus or appendix and still have ok blood work?

Just left ER have acute pelvic/ abdominal pain very severe pain meds not helping; have non obtrusive 8mm left kidney stone (explains flank pain) abdominal pain new, Took Gas X, percocet and Gi cocktail...sent me home, PAIN IS WORSE< Feel like a knife is in my gut, blood work fine, urine showed white and red blood cells ( they dismissed as stones) Want to go back, but afraid they will send me away. HELP