Curious about losing ccs from band 2 weels after fill

Had my first fill on 5-21-08. Doctor said he put in 5 cc. Today I went in for an adjustment because feeling very little restriction, and he said there was only 3 cc in there. Is that normal? Do you always lose ccs that quickly?

I have lost about .2-.3 cc''s with every fill./ I would inquire about losing 3, there could be a reason!