As I have gotten older, I have bemoaned the loss of future time. So much to experience and not nearly enough time left to get it all done. Then I went to a funeral and my perspective has changed.
The man who died, Dick, was 93. He was the second older friend of my husband to leave in just a few weeks. Both of them lived until they died. Both were pilots but Dick didn't learn to fly until he was 77! He flew until he was 90 and continued to come to the airport and fly with others, occationally taking the controls. The other man, Bob, was a glider pilot who made his last flight a week before his death. They were both fascinated with living and God and people and they will be sorely missed.
However, for me, the point was to quit thinking about time. I know I can't "add to my days," but I can use them to the fullest--redeeming the time." God seems to be saying, you have all the time you need so quit thinking about time and live!