Having a fear of entering unfamiliar situation is known as :

Agoraphobia

Specific phobias are the most commonly occurring type of phobia. This group includes irrational fears such as intense fear of a certain type of animal, or of being in an enclosed space. Intense and incapacitating fear and embarrassment when dealing with others characterises social anxiety disorder (social phobia). Agoraphobia is the term used when people develop a fear of entering unfamiliar situations. Many people with agoraphobia are afraid of leaving their home. So their ability to carry out normal life activities is severely limited.