Some suicidal symptoms (due to depression) I borrowed from a website:

Physical symptoms such as dizziness, headaches, stomachaches, neck aches, arms or legs hurt due to muscle tension, digestive disorders. (ruling out other medical causes)
Persistent unhappiness, negativity, irritability.
Uncontrollable anger or outbursts of rage.
Overly self-critical, unwarranted guilt, low self-esteem. Inability to concentrate, think straight, remember, or make decisions, possibly resulting in refusal to study in school or an inability (due to depression or attention deficit disorder) to do schoolwork.
Slowed or hesitant speech or body movements, or restlessness (anxiety).
Loss of interest in once pleasurable activities.
Low energy, chronic fatigue, sluggishness.
Change in appetite, noticeable weight loss or weight gain, or abnormal eating patterns.
Chronic worry, excessive fear.
Preoccupation with death themes in literature, music, drawings, speaking of death repeatedly, fascination with guns/knives.
Suicidal thoughts, plans, or attempts

I think it describes me to a certain extent. Haha. But don't worry I don't think I am into suicide. God loves me man...haha...;) Hmm...but these symptoms seem qte subjective...like almost anyone can have them but it doesn't necessarily mean that they or suicidal or sth.