another thought...if you were ill fitted for your old bike then the muscles you are using now are "out of shape" and need time adjusting (maybe?) I would definitely go back to the fitter and share your issues...it took my fiancee 3 times to get it right and he still then messed with the seat a bit! he also has the fitter check his position periodically to make sure all is good (once a year maybe)

don't forget your stretching either!!!