trans problem

Hi everyone, I just bought a 95 s10 Blazer 4x4 with a refurbished engine and rebuilt transmission, it has less than 500 miles on the trans but it seems to whine fairly loud, it shifts at high rpm's and has no power taking off from a dead stop its as if the gears too high for the motor. Is this common? or should I take the truck to the transmission shop that rebuilt it? Any input would be greatly appreciated!  Thanks, Dave