After I told about the violence, I felt worse, even though I was supported. Is that normal?

Yes, this is absolutely normal. When you have lived with a secret for a long time, you are used to tension, and telling does not lift the burden immediately, but gradually. At first, you become more vulnerable and dependent on others' opinions, and the conversation itself is emotional labor that wears you out. So even with perfect support, there's still a residue—you gave a lot of energy, and now you need time to recover. Listen to yourself: if after the conversation you feel warmth and safety, then you were truly supported.