Now, Lord, what do I wait for?

Now, Lord, what do I wait for? My hope is in You. Psalm 39:7

I've asked myself this question a lot lately, especially this past week. I feel like God is trying to teach me patience by having me wait, and wait, and wait some more. Seriously, I really thought I would know by now what I'm supposed to do after I graduate. I was nervous about not knowing the future when then end of seminary was months away, and here I sit, three weeks out, and I still don't know. I'm waiting, but I have no idea what for. Can I just be honest, and say that I'm frustrated?
I talked to a friend last night about our communication with God. He knows every thought of our minds, so we don't really need to tell Him when we're upset- He already knows this. But should we? Is it ok? Does God want to hear our grumblings? I shared that I feel guilty when I gripe at God, because I should be happy with whatever circumstance He puts around me. My friend reminded me of King David, that he was miserable throughout much of the Psalms, and he cried out to God, and then he praised Him anyway. I spent a lot of time reading through that book last night and today, and I can say with confidence that my hope is in the Lord, and I will continue to wait for Him.
The Lord is my portion, therefore I will wait for Him. The Lord is good to those whose hope is in him, to the one who seeks Him. Lamentations 3:24-25
I praise you because I am fearfully and wonderfully made; your works are wonderful- I know that full well. Psalm 139:14