Assalamualaikum ustadh Everytime I pray I would think somehow through the air of thre fan perhaps my jilbab is going up too much. But I wear loose trousers underneath. am a sister. had someone check. They said nothingshowing. keep thinking I'm missing something in prayer. think im kafir and failed

This is called waswas, and you can seek the help of a psychiatrist. In regards to your clothing, may Allah Subhanahu wa Ta'ala increase you in piety and in treading the path of your mothers, the wives of the Prophet (sallallahu alayhi wa sallam). As for thinking that you are a disbeliever and so on, these are compulsive thoughts known as waswas that you need to ignore, as the Messenger (sallallahu alayhi wa sallam) told us. If you think it is really becoming a problem, you can go to specialists and they can help with that.