If one had a problem completing several fasts this past month of Ramadhan due to was becoming somewhat sick, causing them to bring up mucus from their stomach to the mouth involuntarily. She had tried to spit it out, the frequency was too much so sometimes she swallowed a bit of the mucous, (it did also reach my mouth). Does one have to make Qadha and Kafarra if one was truly sick ?

Is it the same whether the sickness was cause by overeating at iftar time? And is it the same if it could have been aleviated had one only chosen to not lie down for the larger parts of the day.

There is no harm in swallowing one's phlegm or mucous from head and chest as
long as it does not come upto one's mouth. However, if it reaches one's
mouth, the obligatory precaution is that one should not swallow it.