Default returned a defective sd card to walmart - had/has lots of backup data on it..

Hello, well I returned an sd card to walmart that i'd had a couple months - it had slightly broken which is why it wouldn't work correctly.

I had some titanium backups on there, and also a couple nandroids I think - the titanium backups contained my email app with accounts etc., my contacts etc. also.

I'm not trying to be paranoid, but does anyone have any thoughts on this? It seems I read somewhere that an sd card used in one phone, will not read correctly on any other phone, and afterall, the card is defective (why I returned it).
Thanks