Hey, I didn't start studying physio till I was 25 either...lots of us about!

I'm almost qualified (finish in November) so from my limited experience I guess it does sound a bit like tendons snapping/rubbing over the malleolus or crepitus like you can get in the knee?? I agree with alophysio and mention it to your physio (though they may have heard or felt it themselves when they examined you), but I wouldn't worry too much about it.

Best of luck with the rest of your studies I love it even if the prosepct of a job in the UK is non-existant! (why did I leave a stable career for this....? )