I have no idea if that lvl is low or not for your age, but testosterone lvl does goes down with age after 50 it can drop to 50% or lower of what it used to be.

Are you feeling depressed or have less energy than before?, if this is happening try a supplement I used when weight lifting is a ZMA(Zinc monomethionine aspartate and Magnesium Aspartate), Is a balanced suplement of zinc, magnesium and vitamin B6, this will help your body increase its free testosterone levels.

Im sure the people that did your test lvls would have said something it they were worried about it.

Eddy