- speak to a specialist about your difficulty concentrating and see if your symptoms are consistent with ADHD

- failing interviews is completely normal - especially if the interview covers broad theory or includes probability questions which aren't intuitive - practice more interview questions and don't stop interviewing

- don't worry about what your IQ is. One of your scores puts you in the 17th percentile for IQ, the other puts you in the 98th percentile. That tells you a lot about how reliable or useful IQ tests are

- getting your first job in data science is hard. I don't know anything about the job market in Russia but in the UK (and the US from what I hear) there are very few entry-level positions and many (way too many) people who are competing for them