Is this normal?

Not being trans myself I can't fully sympathize or understand what you're going through but my two cents worth is simple. Your dead name has been the name you called yourself for however many years old you. So it may just be a matter of time and practice for your inner voice to start using your new name. You said it was recently that you became trans so maybe just give it some time?

@RUMBUM Yes its normal!

That’s completely normal! It can be hard to get out of old habits, including referring to yourself with specific names or terms that might not be accurate anymore. I’m trans too and I’ve had a similar experience, it’s definitely not just you!