Response: It is possible for there to be signs for the one whose Hajj, fasting, charity or prayer has been accepted by Allaah and they are: the opening of the heart (to good), happiness of the heart and a lighted face. Certainly, for worshipping (Allaah) there are signs that appear on the body, signs that are visible and signs that are hidden. Some of the Pious Predecessors have mentioned that from the signs that a good (act) has been accepted (by Allaah) is that he will be granted the towfeeq to do (yet) another good (act). Certainly the towfeeq of Allaah for him to do more good (acts) after it, is evidence that Allaah (‘Azza wa Jall) has accepted his previous good (acts). He has made it easy for him to do another good act and is happy with him for it.
Shaykh Ibn ‘Uthaymeen
Daleel al-Akhtaa.a yaqa’a feehaa al-Haaj wal-Mu’tamir wat-tahdtheer minhaa – Page 115.fatwaonline.com