Rejoicing with you over the insight the Lord has given you is the right response, and giving Him all honor through Jesus is exactly where praise belongs. What you are describing is much more than a moment of feeling sorry or disappointed about setbacks. Scripture makes a clear distinction between a sorrow that is merely of this world, which in the end brings death, and a sorrow that is according to God, which produces a change of heart and life that leads to salvation and does not need to be regretted. True repentance always means a change.
That is why John preached a baptism of repentance. Going down into the water pictured a death to the old life and a rising to walk in newness of life. It was never meant to be only words or emotion, but a turning that shows itself in fruit. To bring forth fruit worthy of repentance means that the change becomes visible in obedience. Saying we are sorry is not the same as forsaking what was wrong and doing what is right.
You have recognized that for three years, even with good intentions, you put something and someone else before God in the use of your finances, though you knew what Malachi 3:10 teaches about bringing the whole tithe into His house. To see that now and to be grieved about it in a godly way is a gift from God. Only He opens our eyes in that way. The delays and disappointments you have walked through can be part of how He teaches us. Even the Son learned obedience through the things He suffered, submitting His own desire to the will of the Father, and we too learn obedience through suffering in ways we cannot learn otherwise. God uses those hard seasons to train us to yield our lives to Him.
The covenant God made with His people was woven through with this call to obedience. If you hearken to His voice and keep His commands, blessing follows. If you turn aside, blessing is withheld. That principle is still true when He says to test Him in the matter of the tithe and see if He will not open the windows of heaven. Your love for Jesus is proved by keeping His commandments, and putting Him first with what He has entrusted to you is one clear way to do that.
So let this revelation bear lasting fruit. Do not rest only in the joy of the moment, though that joy is real and good, and it is beautiful that those around you were touched by it. Let the sorrow that God has worked in you now work a settled change. Bring the tithe to the Lord first, as Scripture directs, not second or after other loyalties, and walk in that obedience day by day with fear and trembling and with confidence that He is faithful. As you do, trust Him to provide and to lead, and to confirm His work in you by a life that is changed.
May the Lord establish you in this purpose, keep your heart tender to His correction, and fill you with the peace that comes from a clear conscience and an obedient walk before Him in Jesus name.