When you first have your dentures inserted, they may not always feel comfortable. They do need time to settle in. Your tongue and facial muscles also need time to adjust.
You may experience more saliva initially, this is quite normal. You may also experience some sore spots. Do not be alarmed, the dentures just need to adapt to your gums. If the irritation or discomfort continues for a few days, then you may need an adjustment.
Contact your Dental Practitioner, and they can recommend the best course of action.