A stunning portrait of this young lady. She's got the whitest eyes I have ever seen
Your polarising filter can cut down by as much as 2 stops of light, so is not ideal for use when taking portraits, because it will increase the time it takes for you to take your image. Less light reaches the sensor when using a polariser - and that can increase shadows - but, if you are intent on removing reflections indoors, by use of your polariser, half press the shutter button and, looking through the viewfinder, rotate the polariser - you may find you can see the effect it will have on the shadow areas on your subject. That's possibly why some images came out okay - and others didn't.