Am I addicted or depressed?

I have this thing (shyness) and social anxiety, whatever you call it, basically I’m very anxious around people - especially when I have to talk and perform. This has hindered me all my life, I’m 23 right now. 

Over the years because of my avoidance traits in everything (because everything is social) - I developed awful habits. Social media, drugs (weed) and porn addictions. 

Anytime I try to improve myself I’m overwhelmed by thoughts of anxiety and sadness, like constantly all day, to the point I can’t function. and I always end up going to my usual habits to pass time, and end up feeling worse. 

I know it’s probably a bit of both but how much is my “depression” is “withdrawal” systems alongside the social anxiety. Or am I depressed? 

Also what can I do about it. Does it ever go away? What happens if I feel the cause (shyness) isn’t really something I can work on - I’ve tried it’s pretty hopeless