I'd like to help you, but we're going to need some idea what you're using. Hardware / software / something....

ok :)

ok :) , am using MAGIX Music Maker 15 Premium as a software

rode nt1000 mic -> mixer alto amx80 -> PC as hardware

some people say that stereo may not always sound the same as in mono if you know what i mean :?

and am recording vocals over a beat so am checking and learning :)

.... and listening through the PC speakers? headphones? external monitor speakers?

If you can monitor your mix through headphones, a cheap way to monitor in mono might be go to RadioShack and see if they have a headphone adapter that's got a stereo male to a mono female. (whatever size works for you 1/4" or 1/8")

In your recording software, you should be able to pan everything dead-center and if there's any phase cancelling going on you will notice parts missing or weak sounding when they're centered compared to the stereo mix.