Everyone experiences self doubt at times. But we can transform that into positive energy to move forward. If I doubt my ability to do x then the question is what do I need to do to become capable of doing x. Go do that and you keep growing.
When you feel like you are not enough or you are not worthy or deserving you are likely attached to a story you tell yourself about the past.
Perhaps you have regrets that cause feelings of guilt? You then create the story that because you did x you don't deserve y. Maybe you are experiencing remorse or regret, not guilt. What's the difference? Remorse is when you feel sad or contrite about something you have done. Regret is an awareness that you should've done something differently. Guilt is when you have done something that has gone against a value you hold. These are nuances but important. They may all lead to shame and shame is a powerful emotion that keeps you from your vitality and keeps you locked into the past.
Guilt is only useful when you recognize that you have done something INTENTIONALLY to cause harm and you feel repentant for it. The key here is the intentionality of the behavior or act. You can then change by recognizing that this is not how you want to operate in the world.
You may be over-doing guilt and the shame that springs forth from this contributes to a sense of unworthiness that stifles your life. We have all made mistakes, we all have regrets, things we wish we had or had not done. But it's in the past and only our awareness of it and the learning from the event are what we should be taking into the present.
If we don't leave the past in the past we carry it with us, an energetic burden that compromises our creativity and presence in the now.
Imagine putting all your negative or limiting experiences into a bag. The bag keeps growing and yet you don't put it down, you just keep carrying it around with you. After a while it's so heavy you can't move forward. That could be where you're at now.
It's time to put the bag down acknowledging the past, taking any learnings from it and using what you learn to move forward.
I write a lot about Self Love. Self love is the foundation of everything. Without it we don't value ourselves and then we cannot truly value or love others. Self love generates self esteem, self care and self confidence all necessary to thrive in life.
You must change the way you see yourself. Be more compassionate towards yourself so you can see the beauty inherent in the spiritual being that just happens to reside in your body. Get to know that being through self love. When you do you will forgive yourself from any past transgressions, choosing to be an expression of that spiritual being that inhabits your body. You will have access to that powerful energy, unburdened by the past, and step by step you will move forward in your life, going after what makes you happy - because you deserve to be happy.