Soften up your diet and choose easy to chew food like pasta, rice, ground meat and poached fish. Try avoiding crusty breads, tough meats, roasted chicken etc for 1wk. Massage your gums everyday. Swish your mouth with saltwater rinse (1teaspoon of salt to 1 cup of warm water)
See you dentist to have them adjusted. It is common to have to adjust new dentures to remove any spots that are causing discomfort. Get the spots adjusted so you can wear the dentures comfortably.
Go back to the dentist where you go them. Pain and discomfort can indicate that the fit is not quite right. The dentist can adjust the fit of the dentures, so they are more comfortable for you. They can also prescibe something for the discomfort.
It very well could just be that they are new to your mouth and you are getting used to them. If they really hurt you should contact your dentist to have him check the fit out. They could have been fitted wrong and are hurting your mouth.