Relax buddy, China knew damn well that they will be fighting a coalition if it comes to that and hence they are preparing like no other country, give them 10-15 years and you will see them matching with USN in Destroyers, AC's, Submarines and long range Anti-ship BM's, and that is their power. Iran is hitting several countries/Military bases so imagine what China can do specially to the countries like Japan who they resent a lot due to past war crimes.
Also also PN although weak but won't be expecting Chinese Navy to come rescue, all PN will need is information which the most important thing China can provide us, and the rest PN will have prepare for IN. Now that doesn't negate that IN can't do anything but it won't be a one sided fight as many Indians believe, and remember Indians still believe that IAF can handle PAF with just mig/m2k's and SU's while in both 2019-2025 have their booty handed to them. PN surface fleet is weak hence they are building a sizeable Submarine fleet, and as some members pointed out IN has a huge coast line to defend which IN can't properly, PN can/will find loopholes in your ASW reach to sneak a sub or 2 for attacks on your ships/infrastructures. As for Surface fleet will be mostly for defense role as they will try to deny any air attacks on ports like Karachi or Gwadar.
Also, let not forget that Pakistan also have a significant numbers of Coastal batteries with Anti ship missiles ranging between 100-400 km. Pakistan has a very small coastline and for that PN although not super strong but a formidable force and its only keep getting better with time, just a couple of systems that will be joining in next few years are Submarines, Babur Class Frigates, Jinnah Class Frigates, Sea Sultan MPA's and may as
@Ak01 mention SWAT's wont be far behind.