Uh huh, you cannot operationalize missiles out of the blue sky one fine day.It takes YEARS to train the crews, you probably need some hundreds of people to run a missile unit.
Remember, operationalising a missile is not just being able to put it up on the launcher and fire it off - then pose for photographs.
You need to firm up your plans about how the missile would be transported to launch sites, who brings the warheads, by what road do you want to go there, is the transporter ready, survey the launch site, train people to fire it, train people to transport it, train people to put warheads into it, train people to maintain it, train people to repair its accessories, train people to camoflouge it, train people to expose it, provide for enough user trials to make the crews confident about the missile, hide the money you spend on these units, hide the place you store these missiles....if you think you can do all of these and much more required to operationalise a missile without anybody knowing then I tell you : You are so so far away from truth.
Assembling a new missile inside the safe quarters of a lab and test firing it one day is one thing , deploying a missile with hundreds of personnel around it is a another totally different thing.You just cannot escape attention.
Ghauri 3 and Shaheen 3 and whatever missiles you think Pakistan has DO NOT exist.That remains a fact until you can bring credible information otherwise.
Unless that happens, you're merely being hypothetical.