Physical Pain

The reason that physical pain is felt is because one of the different types of nociceptors in the spine send out information particular to the stimulus.  There's thermoceptive nociceptors for heat, mechanoreceptive nociceptors for pressure and polymodal nociceptors, the most sensitive, for both. Stimulation to nerve cell endings cause chemicals in the spine, neurotransmitters, to be unleashed and send signals through the nervous system to trigger response and control the traits of the pain.  
Acute pain is just the pain caused by this process. Chronic pain is pain that is felt after the stimulus is removed. Many people with chronic pain are disabled.  

An outside stimulus, such as intense heat, a cut, or even an exceptionally strong handshake, causes biochemicals on the nerve endings to produce a series of electrical nerve impulses. These impulses pass a "pain message" through the spinal cord to the brain's thalamus, which is located on top of the brain stem and processes the signals to the cerebral cortex. It is the cerebral cortex that interprets the feeling of pain and produces the appropriate reaction, such as pulling the hand away from a hot surface. A number of biochemicals are involved in the experience of pain. Prostaglandins are biochemicals that are released where the injury occurs. These prostaglandins increase blood circulation in the injured area in order to battle infection and promote healing by increasing the supply of white blood cells, antibodies, and oxygen. Prostaglandins also work in concert with other biochemicals, like bradykinin, to increase nerve ending sensitivity and transmit electrical impulses to the brain. The speed at which these electrical impulses travel will vary according to the type of pain. For example, a pin prick may cause only a slight pain, but the impulse it triggers travels.http://science.jrank.org

Abnormal Pain.

 There's also diseases classified as abnormal pain such as Alodynia, in which a person feels pain that wouldn't normally hurt, Hyperalgesia, when one feels pain at a significantly greater intensity than a person normally would, and Phantom Limb, which is a very odd case in which a person still feels a limb that was amputated.

Spiritual Pain

Cicely Saunders, founder of modern Hospice movement coined the phrase “total pain” to refer to physical, spiritual, emotional kinds of suffering commonly experienced by persons with life-limiting illness and their families

Spiritual influences on physical pain:

Spiritual frameworks and religious traditions influence how persons interpret and
experience physical pain.
How mind, body, and spirit are understood in relationship to each other and, in
some cases, in relationship to a deity or deities is important to understand

Usually this framework is broader to include suffering of all kinds, whether its cause is physical or due to other causes.
Some practices that have been proven to help in the management of physical pain
include:
Prayer
Relaxation techniques
Chanting
Ritual cleansing
Acts of atonement
Shamanic treatments
Acupuncture
Herbal remedies

Christine's Personal.

I’ve been dancing since 2 years old doing ballet and tap. Then I started Irish dancing at an early age. Being a dancer holds physical and emotional pain. Emotionally you have to prepare your self and work hard to be the best. You can’t get nervous at competitions because then you will do worse. Although it may be very scary at first and girls seem VERY intimidating you have to believe you’re the best and you are going to win. The judges can tell when you have confidence. I’ve danced at the Nationals, and World Championships and even though I was nervous I still know I had to be brave. I suffer from being very nervous at times and even my peers know that, but I have to try my best. Physically Irish dancing can really affect you. I’ve gotten about 50 or more x-rays a year, 2 MRI’s, I’ve been taken to the bottom of the hospital to inject radiation into me for bone scan, etc. I have had many casts, boot casts, always wrapping my ankle, ace bandages, anything you can think of. Even in school my feet will randomly hurt and my knees will lock ad ill have to limp to class randomly. When I was 12 my teacher pulled me up and I fell down and sprained my ankle, since then it’s never been the same. I went to dance to soon and my foot was not the same and after going to numerous doctors, I got an MRI that showed a minor injury. Then I went back again and it still bothered me and I got a bone scan which showed I had a Salter Haaris injury, which affects the soft tissue around the growth plate. I had to take off a year until my growth plate closed and this really affected my dancing career. I then went back again to dance and had 2 stress fractures so far in the same foot. Doctors tell me my foot will never be the same again and some wonder why I don’t just quit, but dancing is too important for me; I’m not ready to give it up yet. I’ve learned to properly stretch it and know the signs of pain when to lay off. I hope one day my foot will be back to normal and finally be healthy again.