If you have never felt angry at God You must either not believe he exists, be perfect like Jesus or have a perfect life. When humans experience something negative like pain, illness, grief or sadness it is a natural reaction to feel angry. It means you are human. I would say that if you do not experience anger then it is unhealthy. That is not normal. When we humans feel angry we place that anger on either ourselves, other people or God. If you have anger you have to have something to be angry at.
My personal tendency is to first be angry at myself. As I have aged and noticed that being angry at myself is not really a good thing so I start to transition my anger to those close to me and God. This is natural. My husband is gracious towards me and repeatedly I have felt like God has said it is ok. If you want me to be your punching bag go right ahead. I am God. I can take it. My grace is enough for you. Just do not walk away.
At the end of the day when I work through my grief and anger I come to terms with my reality and am reminded who I should really be angry at is the brokenness of our world. When I defer my anger to the brokenness of our world it helps me see through my anger so that I can see ways in which I can work for God to help mend that brokenness. That is ultimately what we should be doing.
The brokenness of our world is what causes discrimination, poverty, illness, crime, abuse, etc. We should not be mad at ourselves. We should not be mad at other humans. We should not be mad at God. We should be mad at the brokenness. Let your anger give you clarity so that you can find a way to fight the brokenness. Ultimately that is what Jesus did. What area of brokenness can you fight against? Maybe that should be part of your ministry. Amen.