13 years ago i was diagnosed with cirrhosis. before then, my whole life, my body temperature was 98.6. since then its 96.7. why is this? and if i feel bad and check my temperature, would a temperature of lets say, 97.5 mean i have a fever?

No, a temperature above 100.4°F would still be considered a fever, even if you feel that your usual body temperature is lower than usual. Good luck.

Probably this has nothing to do with cirrhosis or liver function. Body temperature fluctuates normally during the day, from ~96.5F (typically in the morning) to as high as ~99.5F (usually afternoon or evening). The average in most people is around 98.6F, but some people have lower "set point" (basal temperature) than others. It might change with aging but 97.5F never would be considered a fever.