my cd player seems to be stuck on eject cd?

My car is a cdti 1.4 diesel corsa design and it is fitted with a standard CD player. When I drove it earlier my CD came on automatically as usual but I switched it off pretty much straight away, then after picking my son up I switched it back on and it didn't start playing so pressed eject and now it is stuck on `eject cd` even though the ignition and everything else is switched off. Even if I switch the radio off it comes back on after approx. 30secs and I'm now worried it will drain my battery overnight