Yes you're about 12 days in and the healing of your lungs is well underway. Should you make it to
about 30 days there's a very strong chance of a complete reversal of your condition. Such is the amazing power of fasting.
Just my 2 cents but there is something to be said for going with what your body is telling you rather than any arbitrary number of days. I have actually done a couple of 30 day fasts but it was just a coincidence that it worked out that way. One of these was actually a return to genuine hunger at 29 days, 16 hours followed by 8 hours of the most ferocious testing of my will power i had ever dared imagine.
It is ideal to break your fast feeling good or at least not lousy... and inversely it is very undesirable to break the fast feeling sick... So just as one example if you should happen to be in mid nausea at 30 days it would be far better to ride this out and break your fast once the "crisis" has passed, whether this be 30.5 days, 32.7 or whatever odd number may present itself. Your body does not count days or care about a nice round number, it cares only about where it is in its cycle of detox and healing.
Ivy mentioned wanting to fast to completion (to the return of genuine hunger) and this is the absolute ultimate in terms of allowing the body to cycle completely and indeed perfectly... and as such this is an exceedingly worthwhile goal. The trouble with this, however, is that it is quite unpredictable how long this may take and it could get a bit risky to endure the fast so long. Most people who engage long fasts do not encounter this return of hunger phenomenon.
In my longest fast of 36.5 days i did not reach hunger and i have no idea how much longer i would have had to fast to get there... it might have been 50 or 60 days for all i know, a number of days i was not willing to pursue, especially given the nausea i had suffered through to this point. I settled for riding out a 2nd wave of this nausea and breaking as soon as this had lifted and i was feeling better, hoping perhaps to safely encounter genuine hunger the next time around
.