If u think u may have problems with your appendix. Will it show in a blood test?

Usually not. Appendix problems is the trickiest diagnosis a doctor can make. Sometimes, there is a small elevation in the wbc, but it can be normal. Usually a doctor will press on the lower right quadrant and see if you have any tenderness/pain. The diagnosis is made clinically, and radiologically with a cat scan. Go see your doctor asap if it worsens. Rupture ovarian cysts also masquarade as this too.
Sometimes. Sometimes your white blood cells are slightly elevated. Sometimes a scan can show your appendix is inflamed. But the most certain way of diagnosis is still by being examined and questioned by a doctor. Still sometimes appendicitis is missed or diagnosed as occurring when it is not. A series of timed exams is often needed.