Door won't open

I don't want you to seem like I am being a **** but lets try some trouble-shooting steps.

first make sure the power is on and the machine is working and no sounds are coming from it.

Once pressing the CD-tray to open does it make any sound at all?

The CD-tray may of came off of its track.
If all else fails I would not suggest this but I would say try to manually pull the tray from the console.