Woke up because of severe pain up my right side. this is less painful now but has not gone. could my appendix have burst?

very unlikely: Very unlikely to have a ruptured appendix. Usually the pain associated with appendicitis would wake you up long before its rupture. It is more likely you slept funny or did something strenuous the day before that is now showing up. Also, you should have other signs like nausea, vomiting, fevers and chills if you have appendicitis. There are really unusual cases, and if signs are there, see an md.