Could you try another pin and also add some Serial.print() statement to get the raw analog reading of the pin.
You might also not quite have 3300.0mV as reference. You could measure the voltage and replace 3300.0 with your reading.
And here are also some tips and foremost add a capacitor and/or a 1k resistor (read posts #4 and #7)
Cannot read TMP36 values correctly, please help