First off, you don't know how well you've done until you get the exam result. Worst case scenario is you fail the exam. Big deal. Loads of people fail exams every day. You can re-take. It's not the end of the world. Academia call it 'deferred success'.
Your dream doesn't have to match your Dads dream. Often, parents push their offspring in to fulfilling goals they themselves wished they'd achieved. Or just what they think is best for their kids. They think they're being good parents by directing, but they should really just give their children loving support in pursuing their own route in this (already confusing) life.
Please, don't suicide. I can empathise with your situation because I've experienced similar myself. You're a young person, don't be so hard on yourself. Give yourself a break. Is there a good teacher you can confide in? A good teachers has seen every kind of situation before, and can offer sound advice and help.
As far as education goes, just do your best - that's all you can do! You can't do anymore than that.
All the best. mike25