Pancreas amylase levels up and down?

My 18 year old brother injured his pancreas causing pancreatitis.From what I have research the pancreas is an enigma. He went to the hospital because of the pain. His amylase levels were 1000. He was given an IV and his levels started declining. 5 days later they started him on clear liquids and some foods his levels were at 140. He was released from the hospital. A day later he was in worse pain. We put him back in the hospital, his levels were back up at 700. After spending a day in the hospital his levels went down to 400. He woke up this morning and his levels are at 1000. He has only been on an IV for nutrition since being back at the hospital. Why do his levels keep going up and down? My family has no peace of mind because his levels keeping going up and down. Please help, we are baffled.
Thank you for any information,
A concerned brother.