Does anything indicate to me during prostration that I am prostrating to a pillar or a person, and do I get whispers of apostasy when saying certain words?

This is from Satan's deception and his whispers to turn you away from worshipping Allah and to make you doubt your faith. The obligation is to turn away from these whispers and not pay attention to them. So, whenever Satan puts in your heart that you are prostrating to other than Allah or that you have left the religion, seek refuge in Allah from him and know that you are upon Islam. These thoughts do not affect you and you will not be held accountable for them, based on the saying of the Prophet, may Allah's prayers and peace be upon him: "Indeed, Allah has pardoned for my Ummah whatever they whisper to themselves, as long as they do not act upon it or speak of it."