Fevers spike when an ill person is at rest. The body can heal faster and better while at rest. The fever is good, it needs to break, that is when whatever caused the illness is now killed because of the high temp. Taking Tylenol and other fever reducers only prolong the fever to spike.
Fevers spike at night with EVERYONE. A child’s temp can go scary high, keep her hydrated and give her tylenol as needed.
An Xbox360 mend should be a ‘do it yourself project’ since if you turn the Xbox 360 to Microsoft for mend your wait time would be 4-8 weeks.
If that doesn't work and you are feeling more intrepid, you can disassemble your Xbox360 and further check it for damage. Place the fan face down ( stickers down ) with one fan over the CPU and one over the drive.