My dad just went to the hospital and they think he had a tia? I didn't recognize it so just calmed him and helped him relax for a few hours. Did I do bad?

No. How are you supposed to know what a TIA looks like? There will be other things happening in the future that you won't recognize. This is part of life and how we learn on a day to day basis. Best thing to do is to provide support, prompt attention...And perhaps encourage everyone in the family to take medications as prescribed, exercise and follow good dietary discretion.
No. Tia has only temporary symptoms, but needs full evaluation. You did calm him down, that makes him feel much better. Follow up with his doctor.
See below. Consider it a learning experience. Now you will be alerted to similar events. Go online or read about the major signs/symptoms of stroke/tia so you can react more quickly if there is a next time.