Taking the correct steps on the drawing journey?

Hello! I am by far no advanced drawer. Rather the exact opposite, and I am wanting to change that. I now feel like I am able to take drawing more seriously, instead of just doodling, and giving up because it looks like totally shit.

30 sec:
http://i.imgur.com/SS65Vlp.jpg

1 minute:
http://i.imgur.com/vUxZKw5.jpg

5 minutes:
http://i.imgur.com/WF9tRLH.jpg

12 minutes:
http://i.imgur.com/KQUFN5w.jpg

These are my tries today. What I am most interested is; Will practicing these classes help on different areas in the length? Honestly I'm a bit skeptical that I will get better at drawing not knowing how I should, just that I should.

So many questions pop into my head...
Am I sketching correctly?
Should I 'shade' like I did on 5 minutes, or should I start "semi-linework" like on 12 minutes?

The path before me is just so foggy I have no idea where I am going. :)