That disconnect is a normal kid thing. When you're a kid, bad things can never happen to you because you're stronger and faster and smarter than everyone else with reactions like lightning when this this happens you'll "just" do that.

And also with kids the age you say you were at the time, they don't always have a sense of context and some things simply wouldn't occur to them, like in your case you were "just having fun" and were probably developmentally incapable of realising that it was mind bogglingly idiotic and dangerous and that you were scaring your dad half to death.

_{don't mind me I'm reminded of my youngest doing very similar things because he had no sense of self preservation til he was like 10 or 11 x_x}

So while you're feeling stupid and ashamed of your past terrible behaviour (trust me I've been there and done that too x_x sorry parents!) take comfort in the fact that if you were that young you may not have been developmentally capable of comprehending anything outside what you specifically wanted/were determined to do at that point in time, and also that you grew out of it (some people don't seem to DX) :)

If it's really bugging you that much, just apologise now.

Also if your dad said it was a good life, it must have been a good life.

[random hugs if you feel like it]

ps you're going to find that photo when you least expect it and not remember what you needed it for ;D