Naraic87,
Don't you think the tests are deliberately scheduled that way? Anyone can become an expert and complete the task well if they are given enough time! But Eurocontrol is looking for the people who can not only do the task with 90 minutes preparation but be able to put their (overwhelming) feelings aside and complete the task. This is what a qualified ATCO must do everyday of their working career.
It may sound harsh, but plenty of people can do the test well in the allotted time.
As for age, also not much to say. Eurocontrol have made a decision to try to get a mix of ages in each ab initio group ( as far as possible) because they have more success with these groups. If you met the age criteria and where invited for tests than no more would have been thought about it
By the way Eurocontrol takes people up to the age of 25 (and you were 6 days within this limit) but your profile age says 23 - something is not right somewhere
All the best for the future