the alarm is so loud it makes you wince. the reactor room is bathed in red warning lights as it has been set to consume itself per self-destruct protocol.

The monitors all announce what you already know: the reactor is set to reverse fire its ignition rods to destroy the ship. The sequence cannot be averted once it has begun. Your only hope is to escape before that happens. There could be something of use in here, if you want to take the time to search. If not, move on.