dheyvaththaip peRREnO dhEvakiyAr pOlE
During the time Lord Brahma's son Svayambhuva Manu ruled this earth, Sutapas and his wife Pruchni prayed to Narayana for a long time. When the Lord appeared before them, they asked for a son like Him to be born to them. He blessed them and He Himself was born to them as Pruchnigarba. When they were reborn as Kashyapa and Atiti, He came as their son Vamana. They were reborn for a third time as Vasudeva and Devaki.
In that birth, Devaki was born as the younger sister of Kamsa. After their wedding, a divine voice informed that their eighth son would kill Kamsa. So, Kamsa imprisoned Devaki and Vasudeva and slew every time a child was born to them.
The eighth child was born inside the jail in the month of Avani in the star Rohini in Ashtami thithi at midnight. That child was Krishna. He told them how He was born to them three times. Krishna was later switched with Yashoda's daughter Ekanamsha (an incarnation of Yoganidra/Maya) by Vasudeva, as per the advice of Lord Sriman Narayana.
Thirukkolur Ammal is asking "Did I do severe penance and give birth to the Lord like Devaki did?"