“Do you feel sore after a dental filling?”

Yes you can be sore after a filling. Ask your dentist if the cavity was deep. If it was it may take some time for the tooth to feel better.

Possibly. It depends on a lot of things: location in your mouth, how deep the decay is, whether you even need anesthesia. Ask your dentist to be safe. Don't schedule an important speech or meeting after your appointment, just go home and chill.

Your question suggests you have not yet experienced receiving a dental restoration. I am happy for you that you have been healthy enough to make it 27 years without such an experience.

Is the area needing restoration small and in an easy to reach area?
Is it large and in a difficult to reach area?
Is it upper or lower?

Each of the above questions can affect the answer that would be given. Patients with tight muscles have a higher risk of pain after the procedure. It is more difficult for an anxious, tense, up tight patient to obtain profound anesthesia. Patients with a confident, positive, relaxed attitude will enjoy a much better result. The book GROWING A HEALTHY CHILD, SECRETS FROM A WISE OLD DOC has detailed information you need to avoid ever having to receive a dental restoration again. Dental cavities are close to 100% preventable. The book explains everything in easy to read and understandable language. It is important that you obtain a copy.

Thank you for your important question.

Your jaw may feel a little sore if it was kept open for a while. Usually the dentist will give you a "jaw pillow" called a bite block so you can rest your teeth on that to minimize jaw strain.
The tooth itself usually doesn't feel sore after the filling but may have some slight sensitivity initially but it does fade away.