99% sure it will be the disc, but just giving other things to check / rule out too.

To check a bearing jack the car up. Put your hands at 12 o clock and 6 o clock position on the wheel and rock to see if there is any play. Repeat at the 9 oclock and 3 o clock positions. There should only be a small amount of play, any more than a couple of mm and it can start to cause issues yes.