If we compare this incident with the last escalation in 2019, we can get the answer.
On 19th February 2019, a few days before India planned to drop a bomb on Pakistani soil, Pakistan's prime minister Imran Khan went to the television and warned India in a televised speech that:
If you think that, you will launch any kind of attack on Pakistan, then Pakistan won't just think about a retaliation; but Pakistan will definitely retaliate.
That was proof that Pakistan had an intelligence report well before India was preparing for an attack on Pakistani soil.
Then on 26th February 2019, when India dropped a bomb in the middle of a jungle inside Pakistan, Pakistani military and civilian leadership held a closed-door discussion and planned how they would execute a retaliation.
Therefore, we can see a pattern here, and let us check what happened in the case of the latest missile fire on March 9, 2022.
Firstly, Pakistani intelligence didn't have any information that India was preparing to launch a supersonic missile with an intention to attack. So, they were not panicked.
Secondly, the missile landed without any civilian or military casualties. So, again, Pakistan felt no need for escalation.
Thirdly, the missile was unarmed i.e. there was no warhead. Again, no need for retaliation.
Now, the question is: what if an Indian missile had a warhead?
Again the answer depends on intelligence. If India planned a bona fide attack, Pakistan would have known that well in advance. However, since Pakistan doesn't have the capability to intercept a supersonic cruise missile (in fact, neither does India), Pakistan would have waited, civil-military leadership would have had a consultation, and then they planned an appropriate retaliation.
This would have been the same if India launched a nuclear strike.