Today I braked my bicycle from 50 km/h with my front rim brake and heard a really nasty sound coming from the braking surface of the wheel, and I saw some metal shavings as well. 
The brake has been randomly making these noises for a little while, but this is the first time I've seen shavings. The brake pads and rims are about two months old.

Do you think my wheel is toasted or my brake pads are too hard?

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I have rim brakes. It has been happening for a while, randomly but just the sound, never seen the metal shavings flying from my rim. And yeah, the brake shoes are like 2 months old, as well as the rim.

The rim is aluminium.