First, you should also check the sticks on the ST10 using Hardware Monitor to make sure they operate smoothly and return to zero at center stick.
Second, on a first flight you need to allow the Q to sit on the ground with the motors off for about 13 minutes to allow time for the GPS to update.
Several dealers have the Q500 blades in stock depending on the country in which you live. Also, many countries would regard filming a concert as a commercial flight requiring a special license. The rules vary as well as the enforcement of the rules. In general, flying over people is a bad idea so you would need to stay back a ways to film. I have a simple guideline. If someone asks me to shot a venue or property, it's commercial and I won't do it. If I seek permission to fly a recreational flight and I'm given that permission, then I will.
It's a good idea to fly the first few flights without the camera. There are lots of good tutorials on the Q500 here:
Jeff Sibelius