Mom's PET scan showed

NO cancer. I'm so elated and over the moon, but, at the same time freaked out and scared to death. Also, somewhat confused....she had a PET scan done after seven infusions of carbo/taxol because her last CA125 went up a few points instead of down. Started at 1700 and last one was in the low 80s. It's not reached the "NED" mark. Her gyn/onc said this was the best news. But, why did the number go up? She said there was inflammation around the lung. And that was the only thing on the scan. She did have chest tubes removed a month ago, but, would have thought the inflammation from that would have been gone by now.
Docs words were "you are cancer free"! Does this mean remission even though her CA125 is not 35 or below? Mom doesn't ask any questions so I don't get many answers. Besides the neuropathy in her feet, which is debilitating right now, she feels pretty good. Gets tired easily, but, overall feeling good. Hoping that neuropathy will start to subside now she's not on chemo treatments.