There is no place for emotion, therefore you will not start a nuclear war with India. At this point you are talking about Tactical Nukes with a Thermonuclear armed neighbor. As I indicated the scenario most likely to happen is:
a) War Starts
b) Indian forces over-run you because of collosal conventional superiority
c) Your army starts losing, and is approaching a decision point on nukes
d) Sets off a nuke on Pak soil as a warning that threshold is approaching. Simultaneously US, China etc, start weigjing in to stop further escalation
e) India will stop/ proceed cautiously from that point on any further military objectives.
ANy Pak general who at this point makes the mistake of launching a nuclear weapon on Indian soil will invite a terrible retailiation. Across the world armies know that deterrence works only when people are ready to execute it. Do not make the mistake of imagining it won't. That's not how these systems are designed.