Are you sure your a 34aa? Possible but for your height that combination is unusual not many women have a 34 in underbust and same over would mean big build and no breasts at all.
Check you are wearing the right bandsize by measuring underbust then using that as your bandsize don't add any inches eg underbust 30 bust 34 = 30 c/d
Check you are wearing the right bandsize by measuring underbust then using that as your bandsize don't add any inches eg underbust 30 bust 34 = 30 c/d