Do you advise me to take heed of the warnings and guidance that come to me in an inner feeling, or could that be from the devils?

There is no harm in being cautious and doing good if what you see is a form of inspiration, for it is a type of karamah (divine favor/miracle) that Allah may bestow upon some of His righteous servants, as mentioned in the hadith (definition) about the Muhaddathun (those spoken to by angels). However, a person's righteousness is not judged merely by this occurring to them. Rather, their belief and conduct must be examined against the Shari'ah (Islamic law). If their belief is sound and their conduct is upright, then it is a karamah; otherwise, it is an istidraj (a gradual, deceptive lure towards destruction).