Sending you a welcome hug
You can get complicated grief, have you considered having some therapy to help you work through it? Your Dr may be able to refer you, or find someone in your area who you feel comfortable with
Perhaps you have been moving through the journey a bit but not realised. Feelings in bereavement are so alike anxiety and depression too.
Personally I found being able to talk has really helped me. When you're ready, tell us a more about your brother, or whatever you would like to talk through. Maybe having a go at journaling might help too? xx