Key symptoms are:
- a persistent feeling of sadness and low mood
- loss of interest in the world around you and no longer enjoying things that used to give pleasure
- lack of energy and feeling tired all the time
Other symptoms can include:
- disturbed sleep, such as not being able to fall asleep during the night and then being sleepy during the day
- difficulties with concentration and making decisions
- low self-confidence
- poor appetite or an increase in appetite/"comfort eating"
- feeling very agitated or alternatively very apathetic
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"All it takes is for somebody to see me - and I could just die, just like that. I could want to go to the shop and not come home."
Before the killing, Peters searched the internet for "serial killers", "treatment of child killers in prison" and "premeditated murder".
Arriva Rail North, Greater Anglia and South Western Railway are all affected.