Sounds to me like the person who fitted you didn't do a very good job. The cup size may have been wrong.
Reminds me of when I took my daughter to be fitted for a bra as I had gotten tired of telling her she needed to be fitted and constantly hearing the complaints about how awful "us women" have it having to endure bras.
Well she had refused to be fitted for several years and had always bought off the rack so to speak, so one day I took her into a specialist shop and while she looked for her size I went and talked to one of the assistances asking which was qualified to "fit" then sent her down to see said DD.
DD dutifully went off to be fitted (rather than cause a scene) and suddenly all you could hear in the whole shop was this - OMG OMG your wonderful. Now she wont wear any bra that hasn't been fitted. I have even heard her telling people they must go and get fitted properly. Who'd have known Mothers do sometimes know a thing or two? :lol: