Many people think that a person suffering from agoraphobia basically lives the life of a hermit, committing themselves to their own home, never to emerge. Agoraphobics, actually, fear their feelings of anxiety, no matter where they may occur. Thus, an agoraphobic will consciously avoid a place or a situation where they have felt these feelings of anxiety (i.e outside the home). It does not sound like you are suffering from any such panic-disorder so you are probably not agoraphobic.
Solitude is a state of seclusion or isolation, i.e. lack of contact with people. It may stem from deliberate choice, contagious disease, disfiguring features, repulsive personal habits, or circumstances of employment or situation. Long-term solitude is often seen as undesirable, causing loneliness or reclusion resulting from inability to establish relationships. Furthermore, it might even lead to clinical depression. But some people can thrive on it also, feeling no adverse psychological effects at all.
Maybe you are just a loner, or are lazy?! Maybe you just enjoy your own company. Just be aware though that a sense of alienation from society can develop as a result.