Let me first of all commend you and the others in your church for your willingness to assist people in other parts of the world. Your project not only helped them, I’m sure, but I suspect it also gave your church a new vision for missions.
Let me be honest: We don’t always know why some things happen to us. Yes, from a human point of view it would have been good for you to go on this mission trip–good for you, and good for those you wanted to help. But God is sovereign, and when He closes a door, we can only assume He has another plan for us. Yes, sometimes Satan may be blocking our path–but even then, God can use those situations for His glory.
Do you remember how deeply Paul and his companions wanted to go to a certain area on one of their missionary journeys? That area needed the Gospel, and they had every intention of going there. But the Bible says, “the Spirit of Jesus would not allow them to” (Acts 16:7). Later God’s plan became clear: He wanted them to take the Gospel to Europe instead.
Thank God for watching over you; what if you had had your heart attack 10 days later, in an area with little medical care? But thank God also for giving you other opportunities to serve Him. All around you are people who need your help, and most of all they need Christ. Ask Him to use you right where you are.