dynaryder

First,let's look to the injuries. Hydrogen peroxide should help get the foreign material out of the wound. Just keep putting it on and let the bubbles do their thing. If it's really bad,seek medical attention. From what you describe about your shoulder,you prolly want to go to the doctor anyway.

As for your knees,ever consider kneepads? Seriously,some extra protective gear might be a good idea.

For your second question,only you can decide. I Googled your bike;looks like a pretty fancy piece of kit for someone who considers themselves a newbie. Maybe you should try something less radical and work on your basic skills awhile longer. When I learned to ride a motorcycle,I started on a 200cc trail bike. I've seen plenty of folks get 750cc+ sport bikes for their first ride and then bin them because they couldn't handle the power and/or handling. Not everyone learns at the same pace. Maybe you just need to take it slower.

Hope this helps.