In USA you'll be only viewed as a US citizen despite having Pakistani citizenship.
In Pakistan you'll only be viewed as a Pakistani citizen, despite having US citizenship.
If you owe something to US (like worldwide income taxes), you cannot simply move to Pakistan and not pay them.
If you owe something to Pakistan, you can move elsewhere to avoid it (US, etc), but some fine or punishment may be enforced the moment you come back to Pakistan.
On a positive side, you can benefit from being a dual citizen. As a US citizen, you get 30 days in Pakistan per visit, whereas as Pakistani you can spend unlimited time there. Obviously, US passport allows you to travel to many more destinations visa free compared to Pakistani one.