Hello Àlex, I hope you are doing well. Determining your actual English proficiency level is not as easy as it may seem. However, based on my own experience, I would like to explain some ways in which you can discover how much you have improved your English skills. If you are able to easily comprehend a text that indicates a B2 level, then you have achieved it. To test yourself in each of the four skills, namely reading, writing, listening and use of English, you can find your true level. As far as speaking is concerned, try recording yourself after reading a complex text, such as a summary of the text. After that, listen to yourself and check if you made any mistakes.