Encephalitis or meningitis is a serious brain infection caused by various viruses and bacteria. The symptoms are usually quite severe, and they can include severe headache, neck stiffness, light sensitivity, fever
, and confusion or other alterations in personality. Obviously, if you have symptoms like this you would need to seek immediate medical attention in an emergency room.
Other, more common causes of the symptoms you are experience would include common headache, both tension headache and migraine
headache types. Tension headache tends to cause constant pain, often worse in the back of the neck but also spreading up towards the temples. Migraine tends to cause pain with a more pulsatile pain, often with nausea or visual changes like flashing lights. Both can be diagnoses and easily treated by your primary care doctor
Another very common cause of feeling like you have pressure in the temples and 'swelling' of the head is sinus congestion or a sinus infection. Often there is also nasal congestion and there may be a swishing sensation when you bend forward. Sinus problems can also be easily diagnosed and effectively treated by your doctor.
Start by seeing your doctor - he or she will perform a thorough example and narrow down the potential causes of your symptoms.