24 year old male, acne is somewhat of a recently development in my life.

I am on my 3rd week of the regiment and my acne seems to have worsened, or at least changed into pustules. My acne is all on my forehead, so I only apply BP there. My cheeks are dry cracked and flaky so I have ceased using BP on my cheeks. Is it common for acne to worsen in the first month or so of starting the regiment? It is driving me nuts, all I want to do is pop these little devils. Perhaps I am using too little BP on my forehead. Maybe half a pump.

Advice?