*excuse me, gotta plug in laptop*
fathers aren't very good at showing their feelings. not sure why, but, my dad is the same.
just be happy in the knowledge that your dad does care and is happy for you.
if he wasn't... well... you don't have to think about that because he is.
(if that makes sense.)
He's happy for you, try and forget about it, or if it makes you feel better... apologize
(i spurt verbal diahorrea :lol
Just, don't blame yourself.