Night time pain on the entire side can be due to various reasons, which will need some more investigation.
Can you locate a tooth/ specific area from which the pain emanates? What, if any, aggravates or relieves the pain? What is the intensity, nature and duration of the pain? Any previous episodes of similar type?
Keep noticing.
Next Steps
Consult a dentist and get urself evaluated.
Health Tips
Do not jump into invasive treatment (surgery/ extraction, etc) unless a clear diagnosis is made.