I assume you bought your usual size ~ which is often a mistake.
A good shoe shop (and there are still a few of those around) will be able to help by easing them but wet paper can help.
Try leaving them off for a week and then wearing them for an hour a day, lengthening the wear time every couple of days until they are comfortable or your feet adapt. At least that is the advice from SWWLTBO who used to manage Barretts Oxford Street Branch.
I personally always subscribe to the Duchess of Devonshire's advice to spend as much as one can afford on buying a good bed and good shoes ~ because if you are not in one you are in the other. I don't buy shoes very often, preferring to spend the price of an ordinary pair on having the expensive ones I bought more than 20 years ago properly repaired when necessary.
