You ought to be!
I was chatting with my wonderful girlfriend the other day and we were discussing the future. We talked about hopes, and concerns, and what we thought we wanted to do, and why we wanted to do it. We're both working really hard at the moment (she far more than me) and so as we talked, 'easy options' came to mind. At moments of high stress, when the present seems hard enough without considering the future to be even tougher, the easy option can seem very attractive. But then she said a brilliant thing:
"We shouldn't plan to live lives we feel sufficient for."
What a thrilling idea! I'm sure this is what God wants for us - lives far beyond our own capacity or expectation. This doesn't just mean trying difficult things and hoping that God turns up, it involves seeking God for your future, and trusting in His infinite resource.
I can be tempted to feel anxious when I consider this. I think about my future and feel entirely inadequate. At those times I try to remember another great quote, from Terry Virgo:
"Don't let your imagination go to a place you haven't received grace for yet."
When I think about being a husband, or a church leader, or just older, I feel entirely unready. And I am! God will give me the grace for those things when I get there, not now. The discipline of preparation is part of this, of course, but generally we get "daily bread", not years' supply in advance. Has this not already been the case in my life time and time again - I have trusted Him, He has delivered me!
It is not a sin to feel inadequate, the great apostle Paul seems to have glorified in it (2 Corinthians 2:16, 12:9). We err when we fail to stay close to God in faith at all times.
Feeling anxious? Take it to God (Philippians 4:6-7).
Henry Thoreau commented that, "The mass of men lead lives of quiet desperation." That need not be the Christian's testimony. Don't waste your life. Let us seek and trust our amazing God.