What to do With My Delima.

I have this oppertunity to supbena my Father for a blood test. I was thinking that if it were a match than what would I do? Well first the ball would be in his court to see if he wanted a relationship (father/son) with his only son. To be honest I doubt he will welcome me with open arms. And if he did what would I do? I would like to think that I would have a relationship with him but would I regret it? Damn it I wish this oppertunity never came about. What would you do in my case??