Nah I don't think you'd ever break anything messing around on a skateboard unless you try something rather extreme. I mucked around on skateboards for a bit when I was in highschool, and 99% of the time when you mess up your board goes flying somewhere (like through a window) but you can usually regain your balance and stay upright.
Inline skates on the other hand... When you mess up you usually end up on your hands and knees / arse / head / other body part. Have broken a wrist inline skating, a pair of wrist guards, a pair of knee guards and 3 helmets...
Skateboarding is HARD. Took me like 3 months to be able to do a simple ollie, and was working on doing a kickflip when I gave up... I was a lot more successful on inline skates, within a day I was doing 180's, within 3 months I was doing 360's, then 540's, misty flips, various grabs, riding down stairs, and grinding my way to absolute happiness (although I never really did get comfortable on rails, I much preferred curbs - and my highschool had PLENTY of those) Ah, those were the days. Now I'm old and apparently wiser, and I look back and think "geez I'm surprised I'm still alive..."