my fiance has just had a laparoscopy surgery on her abdonamal that means she had severe cramps in her ovary which could mean u have a chys (siss) on you ovary she was discharged from hospital 5 days later i would look up the symtoms on (n.h.s. com - national health service ) as soon as possible it could be minor or it could be major better safe than sorry :)
Are you running any fever? Nausea/vomiting? Your appendix is in the lower right part of your abdomen and quite often, the pain of appendicitis will start in the middle of your stomach (around the belly button) before "settling" more in the appendix area.
If you start running a fever, the pain increases, you're vomiting or have severe nausea, I'd definitely consider going to the local ER for evaluation.
With your past surgery, it's also possible that you've developed adhesions, which definitely can be painful. If the tests your doctor did come back negative and you continue to have this pain, you may want to see either the surgeon that did your surgery, or at the very least a gastroenterologist for further evaluation.
I hope you feel better soon!