Maybe you went to the wrong psychologist, Gestalt therapy can also help, as the problem is probably rooted in childhood. Management coaching can help with the fear of publicity if you go to a specialist. As far as I know, Darren Chastney has management coaching
https://darrenchastney.com/services/management-coaching/ as one of his specialties, in addition to translation. You can arrange your schedule with him and either meet him in Bratislava for sessions or do them online at a convenient time. Since he has more than 25 years of experience, he will help you not to be afraid of public speaking and to be confident when defending your research paper.