"Is it wrong to feel disappointment with God?"
 Answer:  Disappointment with God is not necessarily wrong or sinful; rather, it is a part of the human condition. The word disappointment  means "a feeling of dissatisfaction when one’s hopes, desires, and  expectations fail to come to pass." When God somehow fails to satisfy  our hopes or does not live up to our expectations, disappointment  inevitably follows. If God does not perform in the manner we think He  should, we become disillusioned with Him and dissatisfied with His  performance. This can lead to a wavering faith in God, especially in His  sovereignty and His goodness. 
When God does not act when we think He should act, it is not because He  is unable to do so. Rather, He simply chooses not to. While this might  seem an arbitrary or capricious act on His part, the exact opposite is  true. God chooses to act or not to act according to His perfect and holy  will in order to bring about His righteous purposes. Nothing happens  that is out of God’s plan. He has control of every molecule that floats  around in the universe, and God’s will encompasses every act and  decision made by every person throughout the world at all times. He  tells us in Isaiah 46:11,  “From the east I summon a bird of prey; from a far-off land, a man to  fulfill my purpose. What I have said, that will I bring about; what I  have planned, that will I do.” Even the birds are somehow part of His  foreordained plan. Furthermore, there are times when He chooses to let  us know His plans (Isaiah 46:10), and times when He does not. Sometimes we understand what He is doing; sometimes we do not (Isaiah 55:9).  One thing we do know for sure: if we belong to Him, whatever He does  will be to our benefit, whether or not we understand it (Romans 8:28). 
The key to avoiding disappointment with God is to align our wills with  His and to submit to His will in all things. Doing so will not only keep  us from being disappointed with God, but it will also preclude  grumbling and complaining about the events that occur in our lives. The  Israelites in the desert griped and questioned God on several occasions,  despite having seen miraculous displays of His power in the parting of  the Red Sea, the provision of manna and quail in the wilderness, and the glory of the Lord that followed them in the form of a pillar of fire (Exodus 15–16; Numbers 14:2-37).  Despite God’s continual faithfulness to His people, they grumbled and  were disappointed with God because He did not act as they thought He  should. Rather than submitting to His will and trusting Him, they were  in a constant state of turmoil and confusion. 
When we align our wills with God’s will and when we can say, with Jesus, “Not my will but yours be done” (Luke 22:42), then we find the contentment Paul spoke of in 1 Timothy 6:6-10 and Philippians 4:11-12.  Paul had learned to be content with whatever God sent his way. He  trusted God and submitted to His will, knowing that a holy, righteous,  perfect, loving, and merciful God would work all things together for his  good because that is what He promised. When we see God in that light,  we cannot possibly be disappointed with Him. Rather, we submit willingly  to our heavenly Father, knowing that His will is perfect and that  everything He brings to pass in our lives will be for our good and His  glory.