Hello and warm greetings!
You sound intelligent.
Is it your heart telling you that you made a mistake? Or is your mind causing you doubt, especially since you were formerly another religion? Could it be that you feel either unworthy, or too smart, to believe in Catholicism? (I don’t know; just asking.

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I may have heard something at Mass today that might help you. I hope I can explain it. I’m paraphrasing the Monsignor’s homily.
(paraphrasing)
Many things we cannot understand, that is the Mystery of God, and (I believe), of the Faith.
What was Adam and Eve’s downfall? The tree of knowledge…they wanted to know everything God knows and understands. That is NOT possible! We cannot make ourselves ‘God’. We shouldn’t even desire to know everything; isn’t that prideful?
My thoughts:
We should know and learn as much as we can. There truly are some things (well, many!) I don’t understand, even if other people do.
I don’t know how a car runs, yet I drive it.
I don’t know how my lungs work, but I breathe.
I don’t know why God loves me and wants me to be Catholic, but He does.
I like to say it like this: my human mind cannot wrap my mind around the Mysteries of the Faith; it is incomprehensible, because I’m thinking like a person, human being. However, I choose to believe with my heart. I know, most of the time we get in trouble for thinking with our hearts instead of our minds, but in this case, it’s highly recommended!
As others have said, pray. Go to Mass whenever possible…weekday Mass has been amazing for me; you know others are there because they want to be, not because of obligation. Pray some more. Do you have an adoration chapel? Surround yourself with other Catholics, if possible. Thank Him as often as possible. Praise Him. Pray some more.
You can get through this, and you’ll come out better for it.
I hope there is some nugget in there that helps.
God bless you and keep you,
Christina