I think the growling is Satan, ticked off that he can’t overthrow the Church, and angry because the time alotted him is running out! The Evil One is simply trying to scare you. Personally, I see the growling as a sign of the Church’s victory!
I’m sure you’ve all heard the prophecy of Pope Leo XIII "THE VISION OF POPE LEO XIII
Exactly 33 years to the day prior to the miracle of the sun, on October 13,1884, Pope Leo XIII had a vision. Here follows an account of that vision:According to the most widely accepted version of what happened, On October 13, 1884, after Pope Leo XIII had finished celebrating Mass in the Vatican Chapel, attended by a few Cardinals and members of the Vatican staff, hesuddenly stopped at the foot of the altar. He stood there for about 10 minutes, as if in a trance, his face ashen white. Then, going immediately from the Chapel to his office, he composed the prayer to St. Michael, with instructions it be said after all Low Masses everywhere. When asked what had happened, he explained that, as he was about to leave the foot of the altar,
he suddenly heard voices - two voices, one kind and gentle, the other guttural and harsh. They seemed to come from near the tabernacle. As he listened, he heard the following conversation:
The guttural voice, the voice of Satan in his pride, boasting to Our Lord:
“I can destroy your Church”
The gentle voice of Our Lord: “You can? Then go ahead and do so.”
Satan: “To do so, I need more time and more power.”
Our Lord: "How much time? How much power?
Satan: “75 to 100 years, and a greater power over those who will give themselves over to my service.”
Our Lord: “You have the time, you will have the power. Do with them what you will.”
and another account:
Leo XIII - a Vision of a Looming Crisis…
On October 13, 1884 Leo XIII had just completed a celebration of Mass in one of the Vatican’s private chapels. Standing at the foot of the altar, he suddenly turned ashen and collapsed to the floor, apparently the victim of a stroke or heart attack. However, neither malady was the cause of his collapse. For he had just been given a vision of the future of the Church he loved so much. After a few minutes spent in what seemed like a coma, he revived and remarked to those around him, “Oh, what a horrible picture I was
permitted to see!”
What Leo XIII apparently saw, as described later by those who talked to him at the time of his vision, was a period of about
one hundred years when the power of Satan would reach its zenith.
That period was to be the twentieth century. Leo was so shaken by the spectre of the destruction of moral and
spiritual values both inside and outside the Church, that he composed a prayer which was to be said at the end of each Mass celebrated anywhere in the Catholic Church. (Prayer to St. Michael).
St Michael the Archangel, defend us in battle. Be our defense against the wickedness and snares of the Devil. May God rebuke him, we humbly pray. And do though, O Prince of the Heavenly God, by the power of God, cast into Hell Satan and the other Evil Spirits that prowl about the world seeking the ruin of Souls. Amen.
(It is said that Satan is prowling about the world like a lion gobbling up souls. Lions also growl).
cin.org/archives/apolo/199811/0050.html