All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and messenger.
First of all, you should know that the matter of the Hereafter is completely different from that of this worldly life, and the grave is the first stage among the stages of the Hereafter. Allaah The Almighty will make His believing Slaves successful in answering the questions of the angels correctly. Allaah The Almighty Says (what means): {Allaah keeps firm those who believe, with the firm word, in worldly life and in the Hereafter. And Allaah sends astray the wrongdoers. And Allaah does what He wills.}[Quran 14:27]
Moreover, it was confirmed that Al-Baraa’ ibn ‘Azib narrated that the Prophet said: "If a Muslim is asked in the grave he will bear witness that Laa Ilaaha Illa Allaah [None has the right to be worshipped but Allaah] and that Muhammad is the Prophet of Allaah, this is the Saying of Allaah (which means): {Allaah keeps firm those who believe, with the firm word, in worldly life and in the Hereafter.}
Therefore, you should take it easy and be firm on faith and the obedience of Allaah The Almighty so that you would be granted Paradise and be secure from the questioning of the angels in the grave. May Allaah make us steadfast and firm with the firm word in this worldly life and in the Hereafter.
Allaah Knows best.