I didnt try to play the punk song yet. Im going to after this post.

The tonic is certainly Bbm in the first section, and Db in the second. I did figure out how to shift the tonic. I was unclear by not stating this in my last post, sorry. I used a I, IV, V progression in the second section. I was not happy with the way it sounded, and heres why.

The first section has an emo feel to it (its not emo.) When going into the second section it sounds harshly happy (the tonal center is very strong in the first section.) There is way to much harmonic contrast.

This is why I was asking about modulation, or cadences. Now I no nothing about cadences with the exception that they are some sort of tool for ending things. So what I think I really need to know at this point is this: Is a cadence an effective tool for what I am trying to do, or do I have to use modulation to change the mood of the song seemingly unoticeable.