Why do I always seem to feel like I have to defend everything I say or do?

The feeling that one needs to defend themselves in everything they say or do is probably rooted in a past traumatic experience that has left and indelible emotional impression. It is a faulty thinking that creates a belief in us that by defending ourselves we will somehow influence others to accept us. However, our present situation Is Rarely the True cause of our ongoing Emotional Pain. Emotional pain and fear in present day-to-day life is seldom solely caused by what is happening in the present situation. Instead, our circumstances stir up painful lie-based thinking, the false beliefs we learned during past life events. If we continue to blame our present situation for emotional pain coming from an earlier event, we will be trapped in an irresovlabe cycle of distress and defeat. Believing that other people or circumstances are the cause of our emotional upheaval empowers them to control us emotionally until they change. When we find freedom from the lie-based thinking held in our memories, we will no longer be stirred up by it and can walk in peace.

because you feel the need to prove everything even when it doesn't need explanation. actions speak..

The way you ask your question makes me think you see this as a negative behavior. It may also be perceived as positive, but it matters to whom do you always feel the need to defend your actions/sayings to. If it's to yourself then it's natural - as we really need introspection and reflection to be able to better act next time. But if it's in front of others, ask yourself what made you feel like you need to defend yourself? What do you feel in those moments? Shame, embarrassment, anger, what emotion? Identify it. The next step is to try to identify who made you feel these emotions before. Once you are able to identify the behavioral pattern and the source of it you'll be able to change it. It isn't easy if you acted like that all your life but you can do it. If you need help, please come back for a 1-on-1 chat. :)

After a while of people doubting you, it's normal to develop a mindset of doubt. Maybe you feel that way because you have been doubted your whole life

A lot of things can push you to feel this way. Your self pride for thinking you are always right, or you fear from being wrong or losing an argument, or being in nature an opposing person for anything, or the most likely option which is being not very open minded and unable to wait and think before responding to be able to have a normal conversation or debate.

It is actually really good to feel that way, because if anyone insulted you, you will have the courage to defend yourself, you have to be thankful, many people have problems and they wish to feel the same way you are feeling and if you want to know why, well, it is caused by past traumatic experiences as a child or as an adult but remember that you are not alone. This behavior is negative and positive so before you defend yourself ask yourself about your feelings because sometimes feelings can cause this

Many people want you to explain your actions in order to protect you and themselves. Maybe your parent or significant other feels as though your actions are dangerous or silly. It may not be right but its the way some people work.

Its not easy and there is no one answer fits all to this. Perhaps you should try thinking about what you say or what you are doing and really thing within yourself is it really something that needs defending or why?

Because I feel like I have to fight for what I say or do, I don't want someone to take that away from me

You might feel that you always need to defend everything that you are say or do as you need to feel justified for your actions.