Squeaky breaks x-reg polo

I'm after a bit of advice please... when ever i break i hear a high pitched squeaking noise. (mainly from the front drivers side) I'm thinking it could be that the break pads need to be changed but i had the car serviced by VW a few months ago but there was no mention from the dealer about needing to replace the break pads/discs. could it be something else? Also, my car has recently become very noisy while driving. (i know that a 1.0l polo isn't the quietest car even at the best of times, but it has got noticeably louder recently) a friend of mine suggested it could be a wheel bearing or ball joint issue. whats the best way could i check to see if that is the case? i had the cam belt changed about two months ago, could that have an effect?