I agree with Gareth.
Assuming that you do not have problems with normal footwear, then it is probably down to the accommodation period necessary to get your boots to fit properly. Hire skates are normally too soft, hence overtightened laces to give ankle support. New skates are normally too hard, and can cause pressure because the leather hasn't softened sufficiently. Either way, foot pain can ensue. Try keeping the laces across your instep looser, and more secure around your ankle. You should be able to wiggle your toes, but your feet should feel secure. When stood off-ice, you should be able to flex your feet sideways only slightly. You may need to readjust your lacing several times to find what is most comfortable for yourself.
Derek