Sometimes after I fully charge the phone, and disconnecting it from the power, the battery suddenly drops to 97%, it is normal? I already made a battery calibration past week. Well, this happened only 2 times.
Yes, this is fairly normal. It happens on most new devices, i have an Evo and it does this constantly. If i'm not mistaken, it comes from the fact that there are multiple cells in the battery, and when it reads 100%, they may not all be fully charged. Thus, when the battery discharges, the first few percent goes quickly, because it wasn't actually charged completely to begin with.
I assume you did something like this for recalibration:
Without this, i find the battery usually drops to 90% pretty quickly, but if yours is only decreasing to 97% in that time, you're probably okay.
The only thing we can really do is hope that these hit it big soon.