So long story short I was suffering from panic attacks and severe depression for 6 month, after endless self-help books and studying everything I am finally cured but there is one strange thing happening to me literally every day

Basically, when it gets dark, I get strong anxiety feeling which I cant shake it off, I cant even explain what I feel or what emotion I am experiencing. This is really hard to explain, but its even harder to describe the feeling, I wake up, everything is fine and normal but when its night my strange anxiety-type feeling goes on. 

Can anyone help or share some stories about this experience?