Is there a certain speed that your wagging starts at?
I started out with a utility trailer, wagging was instantaneous, I could easily lift the tongue with one hand. I stopped 3 times in total, each time I moved weight forward and the wagging started at a higher speed. After the last stop I had no problem traveling at interstate speeds.
You can do a quick check by adjusting your weight. If your fresh water tank is in front of the axles, fill it to add weight to the tongue. The bicycles can be removed and any tanks behind the axles emptied. If the wagging starts at a higher speed you'll know your still tongue lite.
Trailer ballpark setup should be:
ball height to make trailer level
WD bars set to make truck squat equally all around, measure hub center to wheel well opening empty the with trailer and WD's hooked up. Your looking for an equal drop, ie 3/4" or 1 1/2" whatever but the same front and rear.
After this setup there are fine tuning adjustments that can be made but you should be close.