But remember as your new to this and so far you have not picked up all the signs of a engine when its running rich or lean you need to be very careful with your adjustments, as you engine could equally be too lean.
now by adjusting very small increments you are able to see the signs of the engine improving or not without going to far on the needle settings that you do damage, if it does not improve try adjusting the other direction.
But id still go with too rich on low end.