Replying to Beginner Skiing/Terrain questions

This might be a dumb question, but how long should be skiing before you try to do tricks? I started skiing for the first time last season at Greek Peak in upstate NY, this season opened up a couple weeks ago and the few times I went I fooled around a little in the terrain park. I didn't do tricks but was slowly going over small ramps and progressively speeding up and trying to get air. Am I moving too fast? I actually feel like it is making me a better skier as it's a crash course on balance. I really want to try going over the little box but don't want my arrogance to get me hurt lol. Also, I am grown and not a spring chicken if that makes a difference. And does anyone have any exercises they recommend to help with feeling lighter on my feet and helping with the lower back pain from skiing?