Too much pressure

I use a Remstar Pro Series M CPAP with a setting of 5.0 cm.
Last night my machine bumped onto the floor. When I turned it on, the pressure was so great, I could hardly exhale. The display still says 5.0. I normally do not use the c-flex feature because it makes too much noise. Last night I tried it both with and without the c-flex on, but no relief in the pressure.

Right now, the unit has too much pressure and is way too loud!

Is there some kind of a master reset button that will restore factory settings?

Any other suggestions? I can't sleep as it is now, and my wife can't sleep if I don't use my CPAP!

No master reset feature that I know of and I used M series machine for nearly 2 years.
Do you have the provider manual for the machine? If not it can be found here. http://www.apneaboard.com/CPAP%20Adjustment.htm

Was the humidifier attached? If so, was there water in it that possibly spilled over to electronics?
Might take humidifier off and try running the machine to see if possible a connection was loosened and perhaps accounting for sound.
Might try changing pressure setting briefly to see if pressure will settle down upon reset. Like try 6 cm briefly.

If the electronics got wet then it could be fried and causing the pressure to go wild and maybe it is the wild pressure that is making machine so loud.

So I would disengage humidifier first, try machine without humidifier attached, try changing pressure, look carefully at all connections to see if something cracked. Pray no water got into electronics.
Put everything back together and see if pressure will return to normal with minimal sound.

M Series machines were easy to have water spill over into the electronics unfortunately.
The new PR S1 machines have a spill proof plastic tank.

The humidifier was attached, so let me try your suggestions. Thanks!

You might also want to unplug it, wait 20 or 30 secs and plug it back in and see if it resets.

Sounds broken to me, I think a call to the equipment provider is in order. I would let the machine thoroughly dry out in case the machine did get water in it, and try the unplugging method. Good luck, keep us posted.

Good News!

I ran my machine for about 2 hours with no water tank. I also unplugged it for a few minutes, as suggested.

When I started it up last night, it ran just fine.

Thanks to everyone for your suggestions and support!