Psalm 77:3

I remembered God, and was troubled
Either the mercy, grace, and goodness of God, as Jarchi; how ungrateful he had been to him, how sadly he had requited him, how unthankful and unholy he was, notwithstanding so much kindness; and when he called this to mind it troubled him; or when he remembered the grace and goodness of God to him in time past, and how it was with him now, that it was not with him as then; this gave him uneasiness, and set him a praying and crying, that it might be with him as heretofore, ( Job 29:2-4 ) , or rather he remembered the greatness and majesty of God, his power and his justice, his purity and holiness, and himself as a worm, a poor weak creature, sinful dust and ashes, not able to stand before him; he considered him not as his father and friend, but as an angry Judge, incensed against him, and demanding satisfaction of him:

I complained;
of sin and sorrow, of affliction and distress: or "I prayed", or "meditated" ^F12; he thought on his case, and prayed over it, and poured out his complaint unto God, yet found no relief:

and my spirit was overwhelmed;
covered with grief and sorrow, pressed down with affliction, ready to sink and faint under it:

Selah: (See Gill on Psalms 3:2).