At least in the UK (and I think in the US too, but I am not sure) 'I was wasted' is something someone would say if he / she was very very drunk. I don't think that is what was meant here
Could it be something like 'I went in vain', 'I went for nothing'? (may very well be completely wrong - I got this from google which is usually awful for Turkish translations )
hi Lein,
the exact definitions of 'ziyan olmak' are 'to go for nothing', 'to come to naught' and 'be wasted'.
since one of the definitions of 'damaged' is 'to have a bad effect on someone in a way that makes him/her weaker (or less successful)', it'd be ok to use 'damaged' here.