The only problem with starting a new career / life in older age is that NATS will not necessarily send you where you want to go.
It's easy to make new friends and start from scratch when you're 18, maybe not so easy once over 30.
Still worth a try though, especially if your current job doesn't give you satisfaction.
I don't think a half hour visit to the tower will tell you if this is the career for you. It took me 3 years in my current job to decide I wanted out of it (I loved it when I started).
I have aviation experience, several visits to Towers, Approach, ACC, and still don't know whether it's for me or not. But still gonna give it a try, you;ve got nothing to lose.... apart from your current job
Ivor