Hey Rohana

U don’t need to get so panicked about it, unless u know had u been any such sickness before any time in ur life like TB or something, if not it will be routine I had faced the same thing for my mom, she underwent same process and we were sure she didn’t have anything before in her life, but it is not that harsh, if u r on visit (just visit) u can complete ur duration of visit and they won’t allow u to renew ur stay, but if ur visit for employment purpose and u r failed in medical u have to leave the country, because health clearance certificates from outside Qatar are not considered.
Wish u good luck
Jack