There are a wide variety of behaviours and experiences associated with the death of a loved one. Each person will experience not all these. There are major individual differences. The mode of death, personality, social and environmental conditions are factors which affect grief.
When we first hear of death the response is usually one of shock, denial, disbelief and numbness. The shock reactions may last from a few minutes to several weeks.  

FEELINGS THAT CAN BE EXPERIENCED ARE:

SADNESS: usually manifested by crying. Tears are healing so allow them.

ANGER: is frequently experienced after a loss. It can be one of the most confusing feelings for the survivor. We may feel angry towards:
1) The person who has died, the doctor, other health care professionals, other people, their spouse and themselves.
2) Friends who still have their loved ones.
3) God.

GUILT: 1) Many people blame themselves by thinking that something they did or something they neglected to do may have in some way contributed to the death.
2) We often begin to think of all kinds of things we could have done for our loved one.
3) Some parents feel the death is a punishment for past sins and transgressions. Usually the cause for these guilt feelings is irrational thoughts. We need to talk them through with someone and also learn to forgive ourselves.

ANXIETY /FEAR: A general fear that something else terrible and devastating could suddenly happen to hurt us when they know we are so vulnerable.

LONELINESS: Intense feelings of loneliness and emptiness often accompanied by a deep aching desire to hold and touch the loved one again. A feeling of deadness.

FATIGUE: Can be experienced as apathy or lislessness.

THOUGHTS: That are common in the early stages of grieving. They usually disappear after a short time.

CONFUSION: Thinking is confused, difficulty in ordering thoughts, in concentrating and making decisions.

PREOCCUPATIONS: Obsession with thoughts of the person. These coupled with other grief reactions make some people feel they are going to pieces. They fear they are going crazy.

PHYSICAL SENSATIONS THAT MAY BE EXPERIENCED

Hollowness in the stomach. Tightness in the chest. Tightness in the throat. Over sensitivity to noise. Breathlessness, feeling short of breath. Dry mouth. Weakness in the muscles. Lack of energy. A sense of depersonalisation- "I walk down the street and nothing seems real, including myself”

BEHAVIOURS THAT MAY OCCUR

SLEEP DISTURBANCES: It is not unusual for people who are in the early stages of grief to experience sleep disturbances. At night you may go over the event again and again. Sleep disturbances sometime require medical intervention, but for many people it corrects itself unaided.

APETITE DISTURBANCES: Can be overeating or under eating. Under eating is more common.

ABSENT MINDED: Newly bereaved may find themselves acting in an absent¬minded way or doing things that may cause themselves inconvenience.

SOCIAL WITHDRAWL: Some wish to withdraw from other people. Usually a short-lived feeling.

DREAMS OF THE DECEASED: It is very common to dream of the dead person. They can be normal kinds of dreams or distressing dreams or nightmares.

SERCHING AND CALLING OUT: Not infrequently somebody may call out the name of the loved person with an associated comment.

SIGHING: Frequently seen among the bereaved. It closely resembles the physical sensation of breathlessness.

RESTLESS OVERACTIVITY: A need to be always doing something.

CRYING: Tears relieve emotional distress.

VISITING PLACES OR CARRING OBJECTS: That remind the survivor of the deceased.

TREASURING OBJECTS: That belonged to the deceased.

GRIEVING: Is something that takes time. Professionals have attempted to put a time to it based on their studies of bereavement and have quoted two years. This is an average assessment and it can vary greatly from person to person.

TO TALK: Is a necessary precondition to the resolution of grief