Do n95 masks provide ANY protection against asbestos?
It's asbestos, not kryptonite

It's not that toxic, or it would have never attained its status as a popular material in the first place. 

Yes, it turns out to have been a lung-tissue irritant and carcinogen (don't look now: so is fiberglass), but it's so subtle it took 50 years to figure it out, and even then it only was seen in career daily occupational exposure.   

The only reason there's any hysteria at all about asbestos is the lawyer feeding frenzy caused by the existence of trust funds to settle cases: the lawyers are bombing all advertising media trying to find people who will let them take 1/3 contingency fee for easy cases on well-trod ground. 

Meanwhile you have the government trying to communicate to employers (read: cheap and old fashioned) and off-the-curb, never-see-em-again day-labor employees (read: non-English speakers) how to protect themselves from daily, career-long occupational exposure to asbestos, so we don't get any new cases.  Their advice is to use tip-top gear, because that adds up when you do it everyday for years.  In that context, true, you want better than N95, but the way they communicate that to cheap employers is "N95 masks don't work".  

Which is not true at all, in your incidental case. You are much better off having used that mask, mainly due to other risks. 

So if you want to be part of the mesothelioma moral panic, just keep in mind negative thoughts are far more carcinogenic than whatever got through that mask.  

One other thing: Gypsum is fireproof.  Drywall is gypsum and drywall is used for firestops.