Yes, this sounds like it would be an infringement if you use any of the POST IT claims. A patent is on an invention, not the implementation of said invention.
Just a quick example, in case I'm misunderstanding your question, if you invented a four-legged table and got it patented, then I came and said "that four-legged table, but used as a chair instead," that would be an infringement.
The packaging is also irrelevant. That would be a copyright issue in all likelihood, perhaps trademark. But it doesn't impact the patent itself.
Another alternative answer is NO if your invention is about package dispensing POST IT which i think you might be intending too. IN this case you should not use any of the POST IT product or claims.