Psalms 7:14-16 Notice, the wicked one is pregnant with evil, conceives hardship, and gives birth to a lie. 15 He dug a pit and hollowed it out but fell into the hole he had made. 16 The hardship he plans for others comes back on his own head; his own violence comes down on top of his head.
The psalmist is adding a corrective nuance to the image of God as a warrior ready to punish evil. While it is true that God is ready to punish evildoers, he gives his victims opportunity to repent and convert. If anyone is punished for their sins— whether in this life or on judgment day— it will be because of their deliberate actions.
Evildoers are described as pregnant women, as builders of traps. What they conceived and constructed to harm others will fall on them. God is just.